custom forms not showing

Hi,
I have what seems to be a strange problem. Firstly i created a add-in in
vs.net that adds new tasks for a user from a project management app. In order
to view custom data from the external app i've created a custom form. This
form is basically a ActiveX control (written in .NET C#). When the item(s) is
added the message class is set to this custom form. The problem i'm seeing is
that immediately after my add-in loads the tasks, and i click open a task,
the default form shows up instead of custom form. Now If i close my outlook
app and start it up again and then open the same task item, i get the task in
my custom form.

I've even changed the default folder form to the custom form but the problem
still persists.
Anybody seen this issue before.

thanks