Only check for port# after : in ConnectSocketByName

src/netbase.cpp

@@ -464,6 +464,7 @@ bool ConnectSocketByName(CService &addr, SOCKET& hSocketRet, const char *pszDest
     int port = portDefault;
 
     size_t colon = strDest.find_last_of(':');
+    if (colon != strDest.npos) {
         char *endp = NULL;
         int n = strtol(pszDest + colon + 1, &endp, 10);
         if (endp && *endp == 0 && n >= 0) {
@@ -471,6 +472,7 @@ bool ConnectSocketByName(CService &addr, SOCKET& hSocketRet, const char *pszDest
             if (n > 0 && n < 0x10000)
                 port = n;
         }
+    }
     if (strDest[0] == '[' && strDest[strDest.size()-1] == ']')
         strDest = strDest.substr(1, strDest.size()-2);