Question
Is there a herbicide that will kill Bermuda grass that is growing in my Centipede grass without harming the Centipede?

Answer
Hi Dick Mahoney,

A new chemical formula on the market called  'Vantage' is supposed to work.  Visit this web-page for info:
http://www.pestproducts.com/herbicides/vantage.htm

Otherwise, I can only give you an 'educated guess'.
I do not know of any other herbicide for grassy-type weeds that is so specific for Bermuda grass that Centipede grass will go without some effect.  MSMA and DSMA may be another best try I can think of. Wal-Mart and some lawn and garden centers carry MSMA which should be used carefully since it is an arsenic salt.  You should experiment with areas to see how it turns-out. The Centipede grass may be weakened by the treatment, but both grasses will be affected.
If the Bermuda is in dense patches in the lawn, you can use a glyphosate formula (one of the 'Round-Up' chemicals).  
Good Luck!
Jim Gibbs