[imp] Strange MySql problem

[Admin C.Eisma]

Hello,

I'm having a MySql error I never seen before.
I'm using Horde 1.2.4, IMP 2.2.4 with MySql version 3.23.36
I configured Horde succesfully, also the HordeSession works fine with 
the test.php3
The following error appeared when I'm going to the imp/index.php3:

Database error: Invalid SQL: insert into active_sessions ( sid, name, 
val, changed ) values ('ab281898bbbaa6e4fc3f978851bf3203', 
'HordeSession', 
'base64:JHRoaXMtPmluID0gJyc7ICR0aGlzLT5wdCA9IGFycmF5KCk7ICR0aGlzLT5wdFsncyddID0gJzEnOyAkR0xPQkFMU1sncyddID0gJzExJzsg', 
'20010409210847')
MySQL Error: 1062 (Duplicate entry 
'HordeSession-ab281898bbbaa6e4fc3f978851bf3203' for key 1)
Session halted


Is there a way to solve this problem?
Please tell me what to do.

Friendly Regards,



Cesar Eisma