Beat the credit card companies to the punch and they just might be sympathetic.

Write to your card issuers, explaining that your income has been fluctuating widely over the past few months and stating that you intend to repay your debts in full -- a letter much like your question above.

Then offer to pay a regular amount that works for you -- such as $25 a month. Show that you will put your money where your pen is: Enclose a check for that amount and keep paying at that rate. Send your letter and check to the customer service department, not to the place you normally sent payments in the past. (To learn more about contacting credit card companies and handling debt, see Nolo's article Dealing with Debt: An Overview of Your Options.)