When running a webserver on a port other than 80, the port must be specified in the url like this: http://server:port/page/to/look/at. However, when a port is specified, Configuration.pm returns the error message “Does not appear to be a valid URL.” This is difficult to deal with in a situation where the Internet provider is blocking port 80 outbound.
This seems to be caused by the regex on line 101 ( $v !~ /^https?\:\/\/[a-z0-9\.\-]+\//) which does not allow a colon (:) to appear anywhere in the URL after the protocol is specified.
If this were implemented, you might change this
( $v !~ /^https?\:\/\/[a-z0-9\.\-]+\//)
to read this
( $v !~ /^https?\:\/\/[a-z0-9\:\.\-]+\//)
The difference between the two expressions is highlighted in red here:
( $v !~ /^https?\:\/\/[a-z0-9\:\.\-]+\//)