The charity has cut the volume of e-mails flooding its network by a quarter, equivalent to 25,000 fewer e-mails a month, since installing the software six months ago.
Christian Cundall, head of messaging at theSalvation Army, said the organisation had inves-ted in the NetIQ Mailmarshal system following complaints from staff who had received unsolicited adult-orientated spam. Some were so offended that they asked for new e-mail addresses.
"We wanted to block as much spam as possible. Our staff should not receive adverts for Viagra or penis extensions. Some of the e-mails were vile and, as a church, we should not be receiving things such as that," he said.
The charity, which uses Viglen Windows NT servers running Microsoft Exchange and Windows 2000 desktops, said it had taken two days to install and configure the NetIQ mail gateway.
The system downloads two daily blacklists of key words and phrases that appear in known spam. It also rejects e-mails from addresses which do not match the sender's IP address.
"Since we implemented the system, we have discovered that 25% of incoming e-mails were spam. The board was shocked by the figures," said Cundall.
Cundall said a new European directive on spam, due to come into force in the UK next month, and anti-spam laws in America would do little to protect organisations.
He believed spammers were using automatic programmes to harvest e-mail addresses from the Salvation Army website.