Variable scope

Hi All:

I have the following problem:

sub mainsub

  sub1 'cat'

end sub

sub sub1(foo)

  sub2 'dog'

end sub

sub sub2(foo)

    'The debugger tells me that the value of foo is 'cat'!!!!  I want it to be 'dog'.
   Why is the value of foo not local to sub2??

end sub

Thanks,

Yossi