--- src/http.c
+++ src/http.c
@@ -100,11 +100,11 @@
   }else{
     zSep = "/";
   }
   blob_appendf(pHdr, "POST %s%sxfer/xfer HTTP/1.0\r\n", g.urlPath, zSep);
   if( g.urlProxyAuth ){
-    blob_appendf(pHdr, "Proxy-Authorization: %s\n", g.urlProxyAuth);
+    blob_appendf(pHdr, "Proxy-Authorization: %s\r\n", g.urlProxyAuth);
   }
   if( g.urlPasswd && g.urlUser && g.urlPasswd[0]=='#' ){
     char *zCredentials = mprintf("%s:%s", g.urlUser, &g.urlPasswd[1]);
     char *zEncoded = encode64(zCredentials, -1);
     blob_appendf(pHdr, "Authorization: Basic %s\r\n", zEncoded);

All HTTP headers should be terminated by a CRLF combination, not just an LF. Without the proper termination, some servers may reject the header.