diff --git a/uf-headers b/uf-headers
index 085e906..7e55278 100755
--- a/uf-headers
+++ b/uf-headers
@@ -48,5 +48,5 @@ while [ $# -ne 0 -a "$(expr "$1" : '\(.\).*')" = "-" ]; do
 	shift
 done
 
-awk -b -O 'NR%2==1'
+awk -b -O 'NR%2==1' "$@"
 
diff --git a/uf-valid b/uf-valid
index 14ec843..6ef4d68 100755
--- a/uf-valid
+++ b/uf-valid
@@ -164,7 +164,7 @@ awk -b -O -v P="$(basename "$0")" -v WRONG="[^$ALLOW]" -v H=$VAL_HEADERS -v Q=$Q
 		print P ": no FASTA header found at line " NR
 		ERR = 1
 	} 
-	else if ( H && HDR !~ /^>[[:alpha:]]+\|\w+(\|\w+)*(\s+.*)?$/ ) {  # rudimentary syntax check of header
+	else if ( H && HDR !~ /^>[[:alpha:]]+\|[[:alnum:]._]+(\|[[:alnum:]._]+)*\|?(\s+.*)?$/ ) {  # rudimentary syntax check of header
 		print P ": invalid header syntax at line " NR ": " HDR > "/dev/stderr"
 		ERR = 1
 	}