http://www.mpg.de/bilderBerichteDokumente/multimedial/mpForschung/2006/heft02/2_06MPF_20_25.pdf
Sorry it is in German...just picked that up on another website, something I already read in the mag Spiegel...it doesn't take millions of years to make any coal...just a matter of the right circumstances.
May be you can run some translator on the opened PDF-file