InfoPath Dev

Hi,

I am using infopath 2007, browser form. I want to get the pattern dynamically from the secondary data source, and at runtime want to assign that pattern to field. 

I select custom pattern but there is not option to select or get the data from another field.

Any help would be appreciated. This is very important and urgent for our project.

Thanks
Varun

As i didn't get any reply, i am adding more details to this problem with screen shot....

This is how i am writing the expression:

xdUtil:Match(string(Zip), ..\Pattern)

where Zip is current field, and Pattern is field from where i am getting \d\d\d\d\d but intead of taking value, it consider \Pattern as string. THis is where i am not able to figure out how to get value from another field for pattern so that it can be executed on client while running on browser. This pattern is coming from configuration file