multiple approval rules for accounting ranges - what is the execution?

 Dear,

I need to implemenet the following logic with 2 rules  when setting up the Approval Group.
Rule 1:If the Accounting string is '001.5410405.421128.03.00000.000.000' then approval limit should be 500K.
Rule 2:For all other account ranges approval limit should be 10K.

Can somebody suggest how I can do it with one approval group? Or IF I can do it with one approval group?
I tried
Account Range 500000 001.5410405.421128.03.00000.000.000 001.5410405.421128.03.00000.000.000
Account Range 10000 000.0000000.000000.00.00000.000.000 ZZZ.ZZZZZZZ.ZZZZZZ.ZZ.ZZZZZ.ZZZ.ZZZ
both lines as 'Include'
but this didn't work.

About multiple Approval Groups - there was a note stating that
'with Multiple Approval Groups are assigned to the same position....