AdvancedEditTemplate user control postback

[Stepan]

Dear TELERIK,

I'm using custom user control as AdvancedEditTemplate in RadScheduler.

This user control has COMMIT and CANCEL buttons - both server side ones, with different command names: "Update" and "Cancel".

But I'm also planning to add some server side data validation in the user controls's code behind.

Imagine the COMMIT button had been pressed and then my server side validation passed UNsuccessfully.
Is it possible to avoid closing of the AdvancedEditTemplate pop-up, in the same way as if CANCEL button was pressed?

Many thanks!

- Stepan.