[horde] I face a problem in Horde v 3.0.8, that i wanted to configure it with IMAP authentication

[Usha]

Hello All,

I face a problem in Horde v 3.0.8, that i wanted to configure it with IMAP
authentication,  I selected  "Horde" Hyperlink and   the menu  "Horde Setup
>  Authentication". And I selected " IMAP authentication " for "What backend
should we use for authenticating users to Horde? ", but this action fails,
instead the selected option remains in the default value "Let a Horde
application handle authentication".

Refreshing  the test.php page the Session counter increments correctly. Can
any one point out the problem, plz.

Thanks
Usha