oai-pmh harvester breaks on colon

I've been testing the OAI-PMH harvester for Omeka. I've noticed that it seems to not work on repositories that use a colon with a port number in their URL. Whenever the plugin runs into one of these URLs, it hangs and then returns an error stating "String could not be parsed as XML".

If the same repository, however, also allows you to go to the same URL without the port number, the plugin works.

Could you share the URL that's not working for you?

You say the harvester "hangs." Could you estimate roughly how long it's hanging for?