Domain functional level 2003 --> 2008 and TMG 2010 (sp2 rollup 2)

Hi,

We want to raise our domain and forest functional level from 2003 to 2008. All DC's have been on 2008 or 2008R2 for about two years.

I cannot find if there is any impact on TMG 2010 sp2 rollup 2. Does anyone know if this will bring any issues?

Thanks!