Google sent an alert out through various social networking and conventional communications channel this morning that its e-mail service, Gmail, was unavailable to a “small subset of users” this morning and that it was working to correct the problem.

Since the alert went out, Twitter and other social media channels have been buzzing about the outage. There’s no way of telling how many users are affected, but several published reports indicate that it’s also affecting internal Google corporate users. Google said users that map their Gmail accounts to Outlook or Thunderbird are unaffected.

Nominal service was restored by midday, but sporadic outages and performance issues persist, Google said on its blogs.

This is the second outage this week for Gmail users, which includes scores of businesses and universities serviced directly by Google and channel partners. The serial incidents are particularly embarrassing for Google given its promise to provide 99.9 percent accessibility and reliability for paid-users of its Google Apps.

Google Apps is rapidly becoming a favorite cloud-based package of solution providers and value-added resellers. The lower cost and flexibility of Google Apps is giving solution providers an alternative to Microsoft Office to present to their customers.

“We’re seeing enterprise clients with major compliance issues looking to move whole hog to Google Apps because it cuts costs so much and it’s so cheap to maintain,” Ed Laczynski,  founder and CTO of New Jersey-based LTech, told Channel Insider in a recent interview. “It can be a tenth of the spend, and it’s being taken seriously now.”

Google sees the channel as a route to rapidly expanding its Google Apps customer base. The Web services company recently signed a development agreement with MSP Partners to promote Google Apps, which includes a Web-based word processor, e-mail and collaboration tools, to managed service providers. Google is also looking to expand the number of partners in its reseller ranks. Google has more than 400 resellers in its Google Apps channel program.

“We really spent the first six months handling inbound interest in our program, getting early partners up and running, and making sure we had our feet under us and properly supporting everyone,” Jeff Ragusa, channel manager for Google Apps, told Channel Insider. “Now we are getting feedback and assessing what has worked and what hasn’t with the program.”