[ic] handling error

[interchange-users@icdevgroup.org (Interchange Discussion Group)]

I am using the wizard to set up the IC store and got an error when I was doing the shipping handling.  The error is about handling charge, it said:
failed pattern - '3.00' =~ ^\\d+(?:\\.\\d+)?\$ 
Could someone tell me what the error is about and how to fix it?  Thanks in advance for any help.

Sincerely yours,

Tung Tran