HOUSTON, Texas (AP) -- Texas sued the nation's largest Internet-based phone service provider Tuesday, saying Vonage failed to clearly inform customers they cannot automatically dial 911 when they sign up.

The lawsuit follows a case last month when a 17-year-old Houston girl was unable to call 911 on her family's Vonage service during an armed robbery in which her parents were shot and wounded. The girl ran to a neighbor's home and called for help.

The suit was filed under the Texas Deceptive Trade Practices Act and seeks to require Vonage Holdings Corp. to more clearly inform consumers that they must separately sign up for the 911 feature.

"People find out too late that this service might not be available," Texas Attorney General Greg Abbott said at a news conference Tuesday attended by members of the family whose home was robbed.

Vonage spokeswoman Brooke Schulz said customers are informed of the separate activation on two pages on the Internet registration form. She also said that e-mail notifications are sent to customers who fail to activate the emergency service.

"We're at a loss as to what they want us to change, but we're open to any changes they want," Schulz said.

Abbott wants Vonage to include the information in advertising and include a checkoff on the service agreement to make sure people know.

He said information about the type of emergency service Vonage offers is found in the fine print on the Web site, but it is not explained on television commercials or brochures. Customers who sign up for service through call centers also are not told.

The lawsuit seeks $20,000 per violation. Abbott said he did not know how many violations there would be.

Edison, New Jersey-based Vonage has more than 500,000 subscribers.

*Hell hath no fury like a womens anger and damn be the fool who gets in her way*

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