NET statement creating issue when netname contains some specific characters

Hi,

I have the following statement in my svrf runset/rule:

IO = NET M1 vdd

above ststement does not create any issue but if i have the net names like <vdd> or [vdd] as following:

IO = NET M1 [vdd]

during drc its giving the following error:

ERROR: Error INP1 on line 208 (above line) of runset - superfluous or invalid input object: [.

So my question is these special characters are not supported in Net statement? If not any alternative option.

Thanks in advance.