diff --git a/lib/asn1/check-ber.c b/lib/asn1/check-ber.c
index f2a91baaa..88356e340 100644
--- a/lib/asn1/check-ber.c
+++ b/lib/asn1/check-ber.c
@@ -38,7 +38,7 @@
 
 RCSID("$Id$");
 
-static const char *contentdata =
+static const unsigned char *contentdata =
     "\x30\x80\x06\x09\x2a\x86\x48\x86\xf7\x0d\x01\x07\x02\xa0\x80\x30"
     "\x80\x02\x01\x03\x31\x0b\x30\x09\x06\x05\x2b\x0e\x03\x02\x1a\x05"
     "\x00\x30\x80\x06\x07\x2b\x06\x01\x05\x02\x03\x01\xa0\x80\x24\x80"