Both versions work fine for me on XP Pro with Perl v5.8.8...

Update: Added output

C:\progs\perl>perl -p -e "s/(.*?)\.(\w\w\w),/iif([month]>,$1.$2,0) as 
+$2/" temp.
txt
iif([month]>,[01-estimate].jan,0) as jan
iif([month]>,[01-estimate].feb,0) as feb
iif([month]>,[01-estimate].mar,0) as mar
iif([month]>,[01-estimate].apr,0) as apr

C:\progs\perl>perl -p -e "s|(.*?)\.(\w\w\w),|iif([month]>,$1.$2,0) as 
+$2|" temp.
txt
iif([month]>,[01-estimate].jan,0) as jan
iif([month]>,[01-estimate].feb,0) as feb
iif([month]>,[01-estimate].mar,0) as mar
iif([month]>,[01-estimate].apr,0) as apr

C:\progs\perl>perl -v

This is perl, v5.8.8 built for MSWin32-x86-multi-thread
(with 12 registered patches, see perl -V for more detail)

[download]

In reply to Re: Choosing regex delimiters by Not_a_Number
in thread Choosing regex delimiters by xyzzy

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