US politicians have taken the first steps towards imposing restrictions on Google's Gmail service.
Gmail is still being tested
Citing privacy worries, Californian senators have approved a bill that limits Google's plans to scan messages and include ads based on what it finds.
Google said it was working with law-makers on a way to both answer privacy concerns and run a viable service.
Before becoming law the bill will go to California's Assembly for further discussion and possible amendment.
Vote or veto
The Gmail service was announced on 1 April and gives those that use it a gigabyte of storage space to let them archive all their messages.
Google was planning to help fund the service by searching through the text in messages and inserting adverts tailored to the subject of that e-mail.
But earlier this year Senator Liz Figueroa introduced a bill to hobble the freedom Google had to use Gmail in this way.
Some are keen to get using Gmail
Explaining the bill on her website, the senator said that "consumers need to be confident that their Internet-based shopping and communication is private and secure".
California senators in one house of the state's law-making body have backed Senator Figueroa's bill to limit what Google can do with the Gmail messages.
The bill aims to make Google scan messages in real time and ban it from producing records of what people are mailing each other about.
It would also bar the Californian company from collecting personal information from Gmail messages and selling it to other firms.
In a statement Google said it was working with politicians to create a version of the bill that would boost privacy protection in Gmail.
"As is the norm in the legislative process, work still remains on the specific language of the bill," it said.
The bill now goes to California's Assembly for another round of debates and amendments.
The final decision on whether it becomes law falls to California Governor Arnold Schwarzenegger who can approve it or decide to terminate it.