Two members of a German gang who infected more than 100,000 PCs as part of a premium rate telephone scam that netted fraudsters €12m ($15.8m) have been jailed.

An Osnabrück court this week sentenced one of the two men to four years imprisonment, and the other to a 39 month sentence, for their part in planting malware on victims' PCs that dialled premium rate 0190 phone numbers linked to a pornographic website.

The two unnamed men, one aged 31 and the other 35, were part of a gang that racked up €12m in call revenues between July 2002 and September 2003. Prosecution demands to force the duo to pay €7m in restitution to their victims were denied for legal reasons.

The jailing of the dynamic duo is the latest prosecution in the case. Earlier this summer, two other men received suspended jail sentences of 18 and 22 months respectively for their involvement in the scam.

The scale of the fraud, unwittingly supported by German carriers, has prompted changes in the German phone system designed to prevent incidents of similar abuse, German news agency DPA reports.

Graham Cluley, senior technology consultant at anti-virus firm Sophos, said the type of dial-up Trojan scam used by the gang is becoming less of a threat with the growing use of broadband as opposed to dial-up connection by internet users in Germany and elsewhere. ®