idp redirects to wrong sp

[Jukka Hakosalo]

Hi,

We have a strange problem with idp. It redirects to wrong sp. Not to
the application you are going to, but to the previous one.
For example we have app1 with sp, app2 with sp2 and app3 with sp3.
This is how it works:

I go to app1. Idp asks username and password. I get in.

I go to app2 and get in without any problems.

But when I try to go to app3, idp redirects me back to app2.
And when I try to go to app3 again, idp lets me in.

Seems that idp is using wrong session. We tested this with many
applications, Firefox, IE, Fedora and Windows.
The result is every time the same.
What is wrong with our idp?

Regards Jukka