patch

diff --git a/src/dc_configure.c b/src/dc_configure.c
index 06fbf55..1855cc8 100644
--- a/src/dc_configure.c
+++ b/src/dc_configure.c
@@ -38,8 +38,11 @@
 static char* read_autoconf_file(dc_context_t* context, const char* url)
 {
 	char* filecontent = NULL;
+    char* urlcopy = NULL;
+
 	dc_log_info(context, 0, "Testing %s ...", url);
-	filecontent = (char*)context->cb(context, DC_EVENT_HTTP_GET, (uintptr_t)url, 0);
+    urlcopy = dc_strdup(url);
+	filecontent = (char*)context->cb(context, DC_EVENT_HTTP_GET, (uintptr_t)urlcopy, 0);
 	if (filecontent==NULL) {
 		dc_log_info(context, 0, "Can't read file."); /* this is not a warning or an error, we're just testing */
 		return NULL;