Connection refused

[vujadin23]

I don't know what to do...i installed RoundCube on shared hosting.
Installation stuck on 3rd step, IMAP check...i get connection refused error what ever i try.
try host first localhost than 127.0.0.1, than mail.mydomain.com, mydomain.com...for host.
for user: [email protected], only user....nothing.

ssl is disabled,
autocreated user is enabled, but database is empty.

and i can get over telnet, fom my pc...

thanks