No, It's true, most my fiends who used to install pirated application (.sis file) from internet got affected by these viruses and at that time most popular antivirus companies (McAfee, Kaspersky, f-secure) had Symbian versions of their antivirus programs.
Note that these are not computer virii by the definition, as they cannot spread independently. User always need to download the application somewhere and install it themself. The closest analogue would be Remote Access Trojan (RAT) infected Windows PC pirated software.