And in Strawberry 5.16.3.1 

C:\strawberry-perl-5.16.3.1-64bit-portable\scripts>perl -e "/(?<!ss)a/
+i"
Variable length lookbehind not implemented in regex m/(?<!ss)a/ at -e 
+line 1.

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In reply to Re^3: qr/STRING/ fails with certain lookbehind expressions by hdb
in thread qr/STRING/ fails with certain lookbehind expressions by wiewa

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