diff --git a/xmpsdk/src/XMPMeta.cpp b/xmpsdk/src/XMPMeta.cpp
index e6e41b06..6361e506 100644
--- a/xmpsdk/src/XMPMeta.cpp
+++ b/xmpsdk/src/XMPMeta.cpp
@@ -114,7 +114,7 @@ DumpClearString ( const XMP_VarString & value, XMP_TextOutputProc outProc, void
 	
 		// Output the next span of regular characters.
 		for ( spanEnd = spanStart; spanEnd < valueEnd; ++spanEnd ) {
-			if ( *spanEnd > 0x7F ) break;
+			if ( (unsigned char)(*spanEnd) > 0x7F ) break;
 			if ( (*spanEnd < 0x20) && (*spanEnd != kTab) && (*spanEnd != kLF) ) break;
 		}
 		if ( spanStart != spanEnd ) status = (*outProc) ( refCon,  spanStart, (spanEnd-spanStart) );
@@ -124,7 +124,7 @@ DumpClearString ( const XMP_VarString & value, XMP_TextOutputProc outProc, void
 		// Output the next span of irregular characters.
 		prevNormal = true;
 		for ( spanEnd = spanStart; spanEnd < valueEnd; ++spanEnd ) {
-			if ( ((0x20 <= *spanEnd) && (*spanEnd <= 0x7F)) || (*spanEnd == kTab) || (*spanEnd == kLF) ) break;
+			if ( ((0x20 <= *spanEnd) && ((unsigned char)(*spanEnd) <= 0x7F)) || (*spanEnd == kTab) || (*spanEnd == kLF) ) break;
 			char space = ' ';
 			if ( prevNormal ) space = '<';
 			status = (*outProc) ( refCon, &space, 1 );