Index: openssl.scm
===================================================================
--- openssl.scm	(revision 28028)
+++ openssl.scm	(working copy)
@@ -250,7 +250,7 @@
   (let ((ret
 	 ((foreign-lambda*
 	   scheme-object ((c-pointer ssl))
-	   "char ch;\n"
+	   "unsigned char ch;\n"
 	   "int ret;\n"
 	   "switch (ret = SSL_read((SSL *)ssl, &ch, 1)) {\n"
 	   "case 0: return(C_SCHEME_END_OF_FILE);\n"