PowerShell: Update SharePoint multiple value lookup column?!

Hi.

I have some PowerShell scripts that access, update and insert data into various SharePoint 2010 lists. This all works nicely but there is one thing I'm having trouble with. I want to populate a lookup column in a list with multiple values. The column allows multiple values and has many such records inserted manually - but I cannot do this using PowerShell. I can update the lookup column using a single "ID" lookup value - but not with multiple values.

I cannot find any documentation on how to do this using PowerShell. I have seen some examples (C#?) but there's little help in them.

Any suggestions?

Thank you,
Markus