[syslog-ng] Stripping numerals in the destination

I have several server types, like web001-web100 and thumb001-thumb010 or db001-db004 I want each server type to log to the same file and I can't for the life of me figure out a regex for $HOST in the destination statement to strip numerals. Where the first $HOST is below I want to do something like a sed "s/[0-9]*$//" destination d_host { file("/log1/syslog/$HOST/$R_YEAR/$R_MONTH/$R_YEAR-$R_MONTH-$R_DAY" template("$ISODATE <$FACILITY.$PRIORITY> $HOST $MSG\n") template_escape(no) ); }; Thanks for any help you can provide. I've been banging my head against google for hours now...