Android "home"-application locks Nexus S at boot

I have developed an application that runs in a "Kiosk"-mode by presenting itself as a home application.

This application runs on several (50 devices, Nexus S) and is distributed alongside android market. The application also catches the "OnBoot" to complete the Kiosk-illusion.

The problem: Sometimes as the device boots it gets stuck in the boot animation with the animated X, and the support team have so far done a manual Factory Reset, and reinstalled the application. The largest problem I have is that I dont know how to reproduce the error, and thus cannot troubleshoot.

In what circumstances could this occur?
The application tries to connect to my server at boot, perhaps before android gets a 3G-lock? Could this cause the lockup? And if so could it be solved with a simple delay of starting the services?
What shouldn't you do at boot? Best practice etc?

Thankful for help! I will try to answer all questions!

Edit-- The problem is reoccuring, it is not a sporadic incident but instead once it has happened it will happen on every boot.

Solution

I solved the issue by delaying all tasks until user clicked a button "ready to start".