[horde] H3 auth composite

[webmaster at mairie-meyzieu.fr]

HI HORDE MASTERS !
I need a little of your time for a question. I try to make a double authentification with horde. Is it possible ?

I explain my problem. My horde session have an authentification. Users may change their password. IMP should have an other authentification where the login is the same but the password won't be change by users.

Is there a way to do it ?
Is there anybody do it ?

Thanks for all answers.
Aude MB