Consult IRS Publication 590, or speak with your tax adviser, regarding the rules for a short-term loan from your IRA. Verify your account statements. Whether you set up a loan from your 401(k), or take a short-term withdrawal from your IRA,

Your 401k has limits on the amount and the number of withdrawals.
Also, you may have tax issues in the future.

http://www.ehow.com/how_2075545_withdraw-money-fro m-401k.html

The biggest problem I have with the 401k is the part where you pay yourself interest.
Many people believe this is a good idea, but in reality it's bad.

Why?

Because you're taking taxed dollars to pay yourself, then when
it's time to withdraw the money you pay taxes on it again.
That's double taxation.

401k loans are common in most plans. Check with your administrator to see if your plan allows. THey have plan specific rules regarding how many loans, which sources you can borrow from (your contribution, employer contribution, earnings, etc) you can only borrow 1/2 of your vested balance, up to $50,000 in any 12 month period. Repayment is up to 5 years, with payments being taken out of your check . Be sure you can live with the amount being taken from your check during the repayment period as you cannot amend the loan at all once it is issued. If you leave your employer during the loan period, the remaining balance become a distribution if not paid back in a lump sum and is subject to tax and penalty. Small loans are a great feature, but I have seen participants with too many loans, and not enough paycheck left to survive.