The news comes a month after open source software provider Open-Xchange released a new tool to enable iPhone users to have access to Open-Xchange's business-class email, calendaring and collaboration solutions.

iPhone users can get access to their emails, appointments and contacts, anytime and anywhere. A push service ensures that all data is synchronized in real-time.

Users of the original iPhones can also update to the new iPhone 2.0 software to use 1&1's professional communications suite.

"Particularly for small enterprises, 1&1 Microsoft Exchange is a genuine alternative to a dedicated server, and at a fraction of the cost," says Oliver Mauss, CEO of 1&1 Internet. "The iPhone, with its outstanding user concept, has gained many excited followers across the world in a short time. We are very glad that all features of 1&1 Microsoft Exchange are now available on this innovative device".

1&1 Microsoft Exchange is priced from $6.99 per month, and includes an 1GB Exchange account, group functionality tools, such as public calendars, contacts, discussions and task management.

Users will receive a free license for Microsoft Outlook 2007 software. Email addresses from other providers can also be used with 1&1 Microsoft Exchange and the new iPhone software.

1&1 email solutions are hosted within 1&1's high security data centers, where the company oversees security updates and back-ups reducing the total cost of ownership for the service. 

Additionally, users connect to their Microsoft Exchange account via encrypted SSL connections, ensuring secure access to personal data from any Internet-connected computer worldwide.