diff --git a/IkiWiki/Plugin/cvs.pm b/IkiWiki/Plugin/cvs.pm
index 1a432c052..4972efb58 100644
--- a/IkiWiki/Plugin/cvs.pm
+++ b/IkiWiki/Plugin/cvs.pm
@@ -459,7 +459,9 @@ sub rcs_diff ($) {
 }
 
 sub rcs_getctime ($) {
-	my $file=$config{srcdir}."/".shift();
+	my $file=shift;
+
+	local $CWD = $config{srcdir};
 
 	my $cvs_log_infoline=qr/^date: (.+);\s+author/;