diff --git a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/parser/scanner/CompletionInMacroExpansionException.java b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/parser/scanner/CompletionInMacroExpansionException.java
new file mode 100644
index 00000000000..c90cc4db43a
--- /dev/null
+++ b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/parser/scanner/CompletionInMacroExpansionException.java
@@ -0,0 +1,34 @@
+/*******************************************************************************
+ * Copyright (c) 2008 Wind River Systems, Inc. and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *    Markus Schorn - initial API and implementation
+ *******************************************************************************/ 
+package org.eclipse.cdt.internal.core.parser.scanner;
+
+import org.eclipse.cdt.core.parser.IToken;
+import org.eclipse.cdt.core.parser.OffsetLimitReachedException;
+
+/**
+ * Thrown when content assist is used within the parameter list of a macro expansion.
+ * It transports the token list of the current parameter for further use in attempting
+ * a completion.
+ * @since 5.0
+ */
+public class CompletionInMacroExpansionException extends OffsetLimitReachedException {
+
+	private TokenList fParameterTokens;
+
+	public CompletionInMacroExpansionException(int origin, IToken lastToken, TokenList paramTokens) {
+		super(origin, lastToken);
+		fParameterTokens = paramTokens;
+	}
+
+	public TokenList getParameterTokens() {
+		return fParameterTokens;
+	}
+}
diff --git a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/parser/scanner/MacroExpander.java b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/parser/scanner/MacroExpander.java
index f933cf0123d..474eefe48d8 100644
--- a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/parser/scanner/MacroExpander.java
+++ b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/parser/scanner/MacroExpander.java
@@ -170,15 +170,25 @@ public class MacroExpander {
 		TokenSource input= new TokenSource(lexer, stopAtNewline);
 		TokenList firstExpansion= new TokenList();
 
-		firstExpansion.append(new ExpansionBoundary(macro, true));
-		expandOne(identifier, macro, forbidden, input, firstExpansion, null);
-		firstExpansion.append(new ExpansionBoundary(macro, false));
+		TokenList result;
+		try {
+			firstExpansion.append(new ExpansionBoundary(macro, true));
+			expandOne(identifier, macro, forbidden, input, firstExpansion, null);
+			firstExpansion.append(new ExpansionBoundary(macro, false));
 
-		input.prepend(firstExpansion);
-		
-		TokenList result= expandAll(input, forbidden, isPPCondition, null);
+			input.prepend(firstExpansion);
+
+			result= expandAll(input, forbidden, isPPCondition, null);
+		}
+		catch (CompletionInMacroExpansionException e) {
+			// for content assist in macro expansions, we return the list of tokens of the 
+			// parameter at the current cursor position and hope that they make sense if 
+			// they are inserted at the position of the expansion.
+			// For a better solution one would have to perform the expansion with artificial
+			// parameters and then check where the completion token ends up in the expansion.
+			result= e.getParameterTokens().cloneTokens();
+		}
 		postProcessTokens(result);
-		
 		return result;
 	}
 
@@ -455,11 +465,17 @@ public class MacroExpander {
         	case IToken.tEND_OF_INPUT:
         		assert nesting >= 0;
         		if (fCompletionMode) {
-        			t.setType(IToken.tCOMPLETION);
+            		if (idx < result.length) {
+            			throw new CompletionInMacroExpansionException(ORIGIN, t, result[idx]);
+            		}
         			throw new OffsetLimitReachedException(ORIGIN, null);
         		}
         		break loop;
         	case IToken.tCOMPLETION:
+        		if (idx < result.length) {
+        			result[idx].append(t);
+        			throw new CompletionInMacroExpansionException(ORIGIN, t, result[idx]);
+        		}
         		throw new OffsetLimitReachedException(ORIGIN, t);
         		
         	case Lexer.tNEWLINE:
@@ -840,13 +856,12 @@ public class MacroExpander {
 			case IToken.tCHAR:
 			case IToken.tLCHAR:
 				final char[] image= t.getCharImage();
-				for (int i = 0; i < image.length; i++) {
-					final char c = image[i];
-					if (c == '"' || c == '\\') {
-						buf.append('\\');
+				for (final char c : image) {
+						if (c == '"' || c == '\\') {
+							buf.append('\\');
+						}
+						buf.append(c);
 					}
-					buf.append(c);
-				}
 				space= false;
 				break;
 			
@@ -911,6 +926,12 @@ public class MacroExpander {
 			case CPreprocessor.tNOSPACE:
 				replacement.removeBehind(l);
 				continue;
+
+			case IToken.tCOMPLETION:
+				// we need to preserve the length of the completion token.
+				t.setOffset(offset, offset+t.getLength());
+				t.setNext(null);
+				return;
 			}
 			t.setOffset(offset, ++offset);
 			l= t;
diff --git a/core/org.eclipse.cdt.ui.tests/ui/org/eclipse/cdt/ui/tests/text/contentassist2/CompletionTests.java b/core/org.eclipse.cdt.ui.tests/ui/org/eclipse/cdt/ui/tests/text/contentassist2/CompletionTests.java
index 09aa8330ed2..a8310af7764 100644
--- a/core/org.eclipse.cdt.ui.tests/ui/org/eclipse/cdt/ui/tests/text/contentassist2/CompletionTests.java
+++ b/core/org.eclipse.cdt.ui.tests/ui/org/eclipse/cdt/ui/tests/text/contentassist2/CompletionTests.java
@@ -1059,4 +1059,39 @@ public class CompletionTests extends AbstractContentAssistTest {
 		};
 		assertCompletionResults(fCursorOffset, expected, AbstractContentAssistTest.COMPARE_REP_STRINGS);
 	}
+	
+	//	#define INIT_PTR(PtrName)   (PtrName) = 0;
+	//	class CCApp {
+	//	public:
+	//	        int pIShell;
+	//	};
+	//
+	//	int main(void) {
+	//	   CCApp *pThis = 0;
+	//
+	//	   INIT_PTR(pTh/*cursor*/);
+	//	}
+	public void testCompletionInMacroArguments1_Bug200208() throws Exception {
+		final String[] expected= {"pThis"};
+		assertCompletionResults(fCursorOffset, expected, AbstractContentAssistTest.COMPARE_REP_STRINGS);
+	}
+
+	//	#define INIT_PTR(PtrName)   (PtrName) = 0;
+	//	#define COPY_PTR(pTarget, pSource)   (pTarget) = (pSource)
+	//
+	//	class CCApp {
+	//	public:
+	//	        int pIShell;
+	//	};
+	//
+	//	int main(void) {
+	//	   CCApp *pThis = 0;
+	//
+	//	   INIT_PTR(pThis);
+	//     COPY_PTR(pThis->pIShell, pThis->pI/*cursor*/)
+	//	}
+	public void testCompletionInMacroArguments2_Bug200208() throws Exception {
+		final String[] expected= {"pIShell"};
+		assertCompletionResults(fCursorOffset, expected, AbstractContentAssistTest.COMPARE_REP_STRINGS);
+	}
 }
diff --git a/core/org.eclipse.cdt.ui.tests/ui/org/eclipse/cdt/ui/tests/text/contentassist2/CompletionTests_PlainC.java b/core/org.eclipse.cdt.ui.tests/ui/org/eclipse/cdt/ui/tests/text/contentassist2/CompletionTests_PlainC.java
index d1a1895a87e..567dffa8bde 100644
--- a/core/org.eclipse.cdt.ui.tests/ui/org/eclipse/cdt/ui/tests/text/contentassist2/CompletionTests_PlainC.java
+++ b/core/org.eclipse.cdt.ui.tests/ui/org/eclipse/cdt/ui/tests/text/contentassist2/CompletionTests_PlainC.java
@@ -867,4 +867,35 @@ public class CompletionTests_PlainC extends AbstractContentAssistTest {
 		assertCompletionResults(expected);
 	}
 
+	//	#define INIT_PTR(PtrName)   (PtrName) = 0;
+	//	struct CCApp {
+	//	   int pIShell;
+	//	};
+	//
+	//	int main(void) {
+	//	   struct CCApp *pThis = 0;
+	//	   INIT_PTR(pTh/*cursor*/);
+	//	}
+	public void testCompletionInMacroArguments1_Bug200208() throws Exception {
+		final String[] expected= {"pThis"};
+		assertCompletionResults(expected);
+	}
+
+	//	#define INIT_PTR(PtrName)   (PtrName) = 0;
+	//	#define COPY_PTR(pTarget, pSource)   (pTarget) = (pSource)
+	//
+	//	struct CCApp {
+	//	   int pIShell;
+	//	};
+	//
+	//	int main(void) {
+	//	   struct CCApp *pThis = 0;
+	//
+	//	   INIT_PTR(pThis);
+	//     COPY_PTR(pThis->pIShell, pThis->pI/*cursor*/)
+	//	}
+	public void testCompletionInMacroArguments2_Bug200208() throws Exception {
+		final String[] expected= {"pIShell"};
+		assertCompletionResults(expected);
+	}
 }