* Seasonally-adj Dec jobless at 3.15 mln, rate holds at 7.5%
* Adj Joblessness up 3,000 in Dec vs revised Nov 8,000 drop
* Economists upbeat despite expecting a decline of 10,000
* Labour Office sees avg 2011 unemployment down by 244,500
(Adds comments from econ minister, labour office head)
By Joerg Voelkerling
NUREMBERG, Germany, Jan 4 (Reuters) - German unemployment rose unexpectedly in December due to the earlier onset of winter but economists said the underlying trend in the labour market was still positive and would support Europe's largest economy.
Freezing temperatures and snow