Hi Matthew, > HTML::Entities::encode does not encode backslash. Yes it does. > - $formula = &HTML::Entities::encode($formula,"^A-z0-9 !#\$%-;=?~"); How about you try: > - $formula = &HTML::Entities::encode($formula,'^A-z0-9 !#\\$%-;=?~';) -- guy@albertelli.com LON-CAPA Developer 0-7-6-1-