AT Commands PHP

I want to send messages from php by using a GSM modem. I have configured 开发者_开发知识库the modem and tested it using Hyperterminal. Now I want to execute AT commands using php. Is there any open source library available for that, or some other solution?

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Since my php application is hosted on an Apache webserver, I used python, pyserial and mod_wsgi to send the SMS, thanks for all the help.

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I haven't used this myself but someone i know used it a while ago.

http://code.google.com/p/php-serial/