如果是RRSP,那也就算打水漂了。
Nortel can still be sold in US market! The symbol is NRTLQ.
If you have any "Capital Gain", then you will pay less tax over these gains. If after all, you have net Capital Loss, then the amount can be carrier over for future years, to cancel the Capital Gain you may have then. But you may want to check if you can get back the tax you paid in previous years for "Capital Gains", I cannot recall exactly.
Call your broker, tell them about this, then ask them to send you a kind of doc. which they know what it is.