Every dollar counts in a state starved for cash.

Now, gun-toters in Philadelphia, where the deficit is projected to top $1 billion by 2013, are being asked to contribute more to strapped state coffers, too.

The effort certainly won't generate a windfall - more like small change from the city's sofa cushions.

But according to state records, it is long overdue. It also provides a glimpse at tight-fisted city-state relations in hard times.

In 2005, when the legislature amended the law governing licenses to carry firearms, the fee for a five-year license was increased from $19 to $25. The increase, channeled into accounts for license "modernization" and "validation," is supposed to make it possible for even small municipalities to get state grants to buy cameras for making gun-permit photo IDs.

But Philadelphia has not been collecting the $6 increase, a fact brought home to permit-holders with a bracing letter this month from Lt. Lisa King, commander of the Police Department gun permits unit.

"This additional $6 fee was supposed to be collected from all gun-license applicants effective May 1, 2006, [and] is required . . . regardless of whether your application was approved or denied," King wrote. "We apologize for any inconvenience, but, regrettably, if payment is not received by [Jan. 31, 2009], this debt will be placed in collections and could affect your credit. . . . Failure to pay will also result in the immediate revocation of your current firearms license."

Threatened with the loss of their carry permits, gun owners are responding by ponying up, said Lt. Fran Healy, special adviser to Police Commissioner Charles H. Ramsey.

"We made a mistake and I'll take full responsibility for it," Healy said. "We were supposed to increase the fee. Now we need to recoup the money that we should have gotten."

If the sum, estimated at less than $50,000, is not raised through back collection, the state will simply demand the money from the city "and we don't have it," Healy said.

For years, people seeking permits to carry concealed firearms had to prove they had legitimate personal-protection reasons. They had to prove they were proficient with firearms and get doctor's notes certifying that they were physically and mentally able to use them safely.

The state gun law was amended in 1995, making it easier to get a permit. Before the amendment, about 5,000 people were licensed to walk Philadelphia streets packing heat. Three years after the law changed, that number jumped to about 26,000. Healy said it has stayed more or less at that level since.

When the state began pressing its claim to every dollar owed, Healy sought to strike a deal. Years ago, at its own expense, the Philadelphia Police Department bought the same sort of camera-ID equipment made available through state grants, he said.

"We paid for the equipment out of our own pocket. We don't need to petition the state for grants," Healy told the officials with whom he negotiated. "Can you just waive the portion that we haven't remitted to date and we'll call it even?"

A few months later, with the economy crashing, came the answer from state officials. No.

"They want the money," Healy said, adding that the Police Department was also free to apply for state aid to maintain its equipment.

"Once I get the money there," he said, "I'm going to ask for some of it back."