Yes, you can find out what roundcube sees when it talks to your imap server. Telnet to the imap
server on port 143, and issue the command "xyz capability". It will reply with the capability
list. For example:
<hiki> [208] ->telnet mymailserver.com 143
Trying ###.###.###.### ...
Connected to mymailserver.com.
Escape character is '^]'.
* OK IMAP4 Ready ame8 0001deab
xyz capability
* CAPABILITY IMAP4 IMAP4REV1 STARTTLS SORT
xyz OK CAPABILITY
This says my server supports IMAP4, IMAP4REV1, STARTTLS, and SORT.
Good luck,
Mark