In the final days of 2010, the IRS announced that, because of last-minute maneuvering on Capitol Hill, the agency won't be ready to process more than 50 million returns until mid- to late-February. Since most returns demand refunds from the IRS, the delay means millions of taxpayers will have to wait to get their money back.

When Congress approved the big tax bill, attention was focused on the extension of the Bush tax cuts, a payroll tax holiday and restoration of the federal estate tax. But at the IRS, there was plenty of angst about a group of retroactive tax changes that affect 2010 returns. The agency is scrambling to make changes to forms and reprogram computers. But in December, the agency said that it wouldn't be ready on time to accept returns affected by the changes.

The delay applies to all 50 million or so taxpayers who itemize deductions. Since Congress restored the opportunity for taxpayers to choose between deducting state income taxes or state sales tax, the IRS has to revise the Schedule A - the form used by itemizers. It won't be ready to go until Feb. 14.

Millions of non-itemizers will be affected, too - those who can claim the $250 deduction available to teachers and teachers' aides who spend money for classroom supplies or the deduction for up to $4,000 of qualified college costs. These "above-the-line" deductions expired at the end of 2009 but were reinstated retroactively by the legislation President Obama signed Dec. 17.

If you are among the two-thirds of taxpayers who claim the standard deduction rather than itemizing - and you don't benefit from above-the-line write-offs mentioned here - then you can file as soon as you have your W-2 wage reporting form and any other tax paperwork you need. If you filed by mid-January, you should have your refund long before the IRS opens the filing season for taxpayers affected by the delay.

If you are affected, your best bet is to gather necessary information and forms as they arrive, so you can be ready to file as soon as the IRS gives the go-ahead.

- Kiplinger's Personal Finance