I believe that most symptoms of blue smoke on start up point to worn guides or valve stem seals. The former is EXPENSIVE; the latter not as bad because the head doesn't need to be removed.
Though with less than 30k miles and only a 4 (or 5) year old engine, I can't imagine why they'd be worn so soon. If you do a SEARCH and type in "BLUE SMOKE STARTUP" I'm sure you'll find a bunch of info regarding the problem.
2006 E350 w/ 155k miles (Daily Driver)
1993 300E 3.2L Sedan w/ close to about 300k miles
2003 E500 Brilliant Silver (Had 217k miles when totalled!)
1989 300E with 289,000 miles (had for <1 yr while in HI)
03 CLK 500 cabrio (Mom's)
2006 C230k (Dad's)
1999 S420 (Mom's/Dad's)
2000 C230k Sport sedans
2001 CLK320 Cabrio (Mom's)
1995 C280 My First Mercedes-Benz... (155k miles. EXCEPTIONAL AUTOMOBILE. Was Very hard to let go of!)