No. The problem is that MLPs can produce UBTIs - and UBTIs over $1000/year will cause you to file and pay taxes on income in a 401K or IRA on those UBTI dollars [and that is in the year in which the UBTI exceeds $1000 - not the year in which the money is withdrawn].
Most MLPs produce negative UBTIs - so that is not a problem for MOST. but MMP has a recent history of producing strongly positive UBTIs after it is held for a short period of years.
I can not test the link in preview mode - so in case the link does not work, the info is posted on the EPD board in the thread 'What is the MLP specific "due diligence"?' that was posted on 9-25-09 [so you will have to go to the first page of the prior/old messages to find that thread]
If you are new to MLPs, then read the whole thread [at least those messages of little use are short] and not just the two messages to which I gave a link. I failed to generate an interest in other investors adding to the info I gave - so the thread fell short of delivering all the information I hoped to generate in the intro.