--- icu.orig/source/common/uloc.c	2007-12-12 13:57:24.000000000 -0500
+++ icu/source/common/uloc.c	2012-01-21 19:54:19.603574549 -0500
@@ -1716,7 +1716,7 @@
         /* Check for EURO variants. */
         sawEuro = _deleteVariant(variant, uprv_min(variantSize, (nameCapacity-len)), "EURO", 4);
         len -= sawEuro;
-        if (sawEuro > 0 && name[len-1] == '_') { /* delete trailing '_' */
+        if (sawEuro > 0 && len > 0 && len <= nameCapacity && name[len-1] == '_') { /* delete trailing '_' */
             --len;
         }