--- gawk-3.1.5/eval.c.wconcat	2006-02-10 22:45:26.000000000 +0100
+++ gawk-3.1.5/eval.c	2006-02-10 22:46:01.000000000 +0100
@@ -1176,6 +1176,7 @@
 			memcpy(l->stptr + l->stlen, r->stptr, r->stlen);
 			l->stlen += r->stlen;
 			l->stptr[l->stlen] = '\0';
+			l->flags &= ~WSTRCUR;
 		} else {
 			char *nval;
 			size_t nlen = l->stlen + r->stlen + 2;