After transcripts of some voicemail messages from Google Voice users appeared in search results, Google has modified the telephony management service to prevent this from happening, the company said.

Since its launch in March, Google Voice allowed users to post voicemail transcripts on public web pages, so that they could share the content of the messages with others.

While Google Voice users will be able to continue this practice, the voicemail text will now be off limits to search engine crawlers.

"We can certainly understand people would want to make their voicemails public on their own sites, but not necessarily searchable directly outside of their own website. We made a change to prevent these voicemails from being crawled so their content will not be indexed," a Google spokeswoman said via email.

Google apparently implemented the change at least several weeks ago, according to this entry in the Google Voice Help Forum.

However, the issue came to light on Monday when technology news site Engadget spotted some of the voice mail transcripts in search results.

When Google acquired it in July 2007, Voice was called GrandCentral. At the time, Google closed new registrations to the service. Google relaunched it with the new name in March this year, but still kept it as a private beta available only via invitations from Google. Earlier this month, Google started allowing existing users to invite a small number of their friends to join.

Google Voice is an online service designed to simplify the management of telephony tasks by, for example, generating automated transcripts of voicemail messages. Google Voice users get a phone number that they can keep "for life" and link to other phone accounts, such as their home phone, cell phone and office phone. That way, a person's contacts only need to remember one phone number that, at least in theory, will not change. Google Voice also lets users make free phone calls in the US and Canada and low rate calls elsewhere, and allows them to record phone conversations.