diff -urpN memdbg2/src/rules.c memdbg1/src/rules.c
--- memdbg2/src/rules.c	2013-05-17 20:54:32.781250000 -0500
+++ memdbg1/src/rules.c	2013-05-17 21:25:50.500000000 -0500
@@ -247,7 +247,7 @@ static void rules_init_class(char name,
 /* allocation was removed  (JimF, 2013)                                    */
 char *userclass_expand(const char *src)
 {
-	unsigned char _src2[0x100], *src2=_src2;
+	unsigned char _src2[0x100], *src2=_src2, dst_seen[0x100];
 	char dst_tmp[0x200];
 	char *dst = dst_tmp, *dstend = &dst_tmp[0x100];
 	int j, br = 0;
@@ -267,11 +267,15 @@ char *userclass_expand(const char *src)
 	dst = dst_tmp;
 
 	// pass 2: parse ranges between brackets
+	memset(dst_seen, 0, sizeof(dst_seen));
 	while(*src2 && dst < dstend) {
 		if (*src2 == '\\') {
 			if (src2[1]) {
-				*dst++ = *++src2;
-				src2++;
+				if (dst_seen[src2[1]] == 0) {
+					*dst++ = src2[1];
+					dst_seen[src2[1]] = 1;
+				}
+				src2 += 2;
 				continue;
 			} else {
 				return NULL;
@@ -291,18 +295,35 @@ char *userclass_expand(const char *src)
 				continue;
 			}
 			if (*src2 == '-' && src2[1] && src2[1] != ']') {
-				if (src2[-1] < src2[1])
-					for (j=src2[-1] + 1; j < src2[1]; j++)
-						*dst++ = j;
-				else
-					for (j=src2[-1] - 1; j > src2[1]; j--)
-						*dst++ = j;
-				*dst++ = *++src2;
-				src2++;
+				if (src2[-1] < src2[1]) {
+					for (j=src2[-1] + 1; j < src2[1]; j++) {
+						if (dst_seen[j] == 0) {
+							*dst++ = j;
+							dst_seen[j] = 1;
+						}
+					}
+				} else {
+					for (j=src2[-1] - 1; j > src2[1]; j--) {
+						if (dst_seen[j] == 0) {
+							*dst++ = j;
+							dst_seen[j] = 1;
+						}
+					}
+				}
+				++src2;
+				if (dst_seen[*src2] == 0) {
+					*dst++ = *src2;
+					dst_seen[*src2] = 1;
+				}
+				++src2;
 				continue;
 			}
 		}
-		*dst++ = *src2++;
+		if (dst_seen[*src2] == 0) {
+			*dst++ = *src2;
+			dst_seen[*src2] = 1;
+		}
+		++src2;
 	}
 	*dst = 0;
 	if (br) {