More than 7 polygons overload cpu

[Lapo Pieri]

I've just updated from debian (unstable) to 20110918 and I've found that when more than 7 polygons are present on the board cpu load rise to near 100% and all become slow; if no mouse movement are done cpu load go back to zero.
I've verified that the same appen to fresh downloaded source tree wit git.
No other settings ("thin draw", "thin draw poly", etc...) solve this.
Version 20091103 work fine in this case.
To reproduce the problem just draw 7 polygon (or even rectangle) and than add the 8th.

I think it's a bug...

Lapo