Darcs could be a bit more intelligent with how it interprets colons 
in repository URLs. In particular, we should follow the example of 
git and search for the ":" to signal that this is an ssh URL only up 
to the first "/".

That is, the following should succeed and create a local repo named 
"./screened:clone":

> darcs clone ./screened ./screened:clone

Currently this gives me:

ssh: Could not resolve hostname ./screened: Name or service not 
known
Refusing to overwrite existing file or directory.

The following patch sent by Ben Franksen <ben.franksen@online.de> updated issue issue2645 with
status=resolved;resolvedin=2.15.0 HEAD

* resolve issue2645: search for ":" to detect ssh URLs only up to the first "/" 
Ignore-this: 8f056d0515250a09fea156e1a4c05f90b9874c1c37bf7d543591ba636773b976007978fe152a336c