Inmates have inboxes at more than 20 federal facilities, and all 114 U.S. prisons are expected to have e-mail for inmates by 2011.

The program, started several years ago, has reduced the amount of paper mail, which can hide drug and other contraband.

Just as important, officials say, e-mail helps prisoners connect regularly with their families and build skills they can use when they return to the community.

For Garcia, 38, that means learning the computer.

"Let's just say that my previous employment didn't require it :o)," he joked in an e-mail.

Inmates aren't given Internet access, and all messages are sent in plain text, with no attachments allowed.

Potential contacts get an e-mail saying a federal prisoner wants to add them to his or her contact list and must click a link to receive e-mail, similar to accepting a collect call.

Prisoners can send messages only to those contacts, who can change their mind at any time and take their name off the prisoner's list.

Scott Middlebrooks, warden at the Coleman federal prison northwest of Orlando, Fla., said his inmates sent more than 3,200 messages and received about 2,800 a day last month through the system, which is called Trulincs and is run by Advanced Technologies Group Inc. of Iowa.

The Federal Bureau of Prisons says the system is funded with some of the proceeds from prison commissaries and by the 5 cents per minute that inmates pay while composing or reading e-mail.

Security, of course, is a concern.

That's why the messages can be screened for keywords that suggest an inmate may be involved in a crime, or read by a corrections officer, just like paper letters. That can create a delay between sending and receiving messages.

Without analyzing the program specifically, said Bruce Schneier of the security firm BT Counterpane, he can't tell whether inmates could abuse their e-mail privileges.