A Google spokesman confirmed on Monday that accounts for a "small number" of users were unavailable for a number of hours on Sunday. He declined to specify the exact length of the outage, its nature or how many users were affected.
"We have since fixed the problem, and all users can log in and resume normal use of Gmail at this time," he said.
Gmail is Googles Web-based e-mail service that it launched in beta in April. The service is not yet available to the general public but only by invite by other Gmail users.
Sporadic outages are nothing new to Web-based e-mail services. Most recently, users of Yahoo Inc.s Web e-mail service faced sporadic access to their accounts when the Internet company relaunched Yahoo Mail in June. Microsoft Corp.s MSN Hotmail service also has been known to have outages for some users.
Google has not said when it will make Gmail generally available. The service drew widespread interest because it provides users with a gigabyte of e-mail storage for free and offers a Web interface focused on searching and archiving messages rather than organizing them in folders or deleting them.
Yahoo and MSN, among others, have responded by increasing their storage limits. Yahoo also is preparing another update to its e-mail service after acquiring e-mail startup Oddpost Inc. last week.