Postgresql instr that works with unicode

Postgresql instr that works with unicode

I tried to do an instr in a postgresql query and then realized that it
doesn't seem to have an instr function.
Found this url
http://www.postgresql.org/docs/9.1/static/plpgsql-porting.html#PLPGSQL-PORTING-APPENDIX
that shows how to implement instr in postgresql's plpgsql language.
However it does not seem to work with unicode varchar columns, since I get
the following error:
ERROR: character with byte sequence 0xe4 0xb9 0xa6 in encoding "UTF8" has
no equivalent in encoding "WIN1252"
even though I have used
SET client_encoding = 'UTF8';
on my client. Anyone know how to accomplish an instr with unicode?