The service costs ú25 to sign up for, with a monthly service rental cost of ú10. Usage charges are on top of this for inbound (e-mail to SMS) messages. No surcharges are imposed for outbound (SMS to e-mail) messages.

SMS is the name of the text messaging system found on most digital cellular phones. Using the digital control channels, text messages, each of up to 160 characters long, can be sent on a network to mobile basis. Where the mobile supports the facility, either by PC or PDA (personal digital assistant) connection, or via direct input on the phone's keypad, SMS is also supported on a mobile-to-mobile or mobile-to-network basis.

The Airmail service works on a two-way basis, with inbound messages addressed to @dres.com being routed to the user's digital mobile and, optionally, reflected to a user's chosen mailbox on another Internet-addressable system.

Mungo Amyatt-Leir, DSR's marketing director, told Newsbytes that the service is free for outbound messages, apart from standard charges imposed by the network for mobile originated SMS messages -- 10 pence each on Cellnet and Vodafone and five pence each on Orange. Amyatt-Leir noted that the Hutchison Orange SMS charges are currently being waived, but charge introduction is expected within a few weeks.

Inbound messages -- e-mail to SMS -- cost five pence per message on Orange, eight pence per message on Cellnet, and 10 pence per message on Vodafone. To prevent wallet or purse fatigue, DSR allows the user to select the maximum number of SMSs that will be sent to the mobile per e-mail message.

"This prevents someone getting a very large e-mail or e-mail attachment on their mobile," Amyatt-Leir said, adding that the optional reflecting of messages to other system mailboxes allows users to retrieve large messages when they want, using a modem.

"On Vodafone, since there is a reverse charge facility for SMS, the 10 pence charge will appear on the user's Vodafone bill. With Orange and Cellnet, to keep matters simple on the billing front, we have a variety of plans, such as Message 50, which allows users to pre-pay their SMS charges on their monthly bill," he said.

According to Amyatt-Leir, while the Airmail service is UK-centric, subscriptions can be obtained by foreign digital cellphone users, provided their digital network provider supports inter-system SMS messaging. Similarly, when a digital cellphone user is roaming, subject to roaming agreements, the SMS messages will follow them to their roamed country, at no extra charge.

Amyatt-Leir told Newsbytes that the company is also looking at setting up Airmail services in other countries with digital cellular nets with SMS facilities. The system uses the company's SMSGate, a gateway SMS system that Amyatt-Leir claims is being tested by a number of foreign digital cellular networks.

Connection between the SMSGate and the three UK digital nets is via a combination of X.25 and dial-up links, Amyatt-Leir said.

Further details of the Airmail service can be found on the company's home pages at http://www.airmail.co.uk .

(Steve Gold/19960619/Press & Reader Contact: DSR, tel +44-171-5840084, fax +44-171-584-5442, Internet e-mail airmail@dsres.com)