diff --git a/git-ftp/Makefile b/git-ftp/Makefile
index 40ca0fa..60c164b 100644
--- a/git-ftp/Makefile
+++ b/git-ftp/Makefile
@@ -3,6 +3,7 @@ SHELL=/bin/sh
 
 DESTDIR?=/usr/local
 prefix?=${DESTDIR}
+mandir?=$(prefix)/man
 
 # files that need mode 755
 EXEC_FILES=git-ftp
@@ -24,12 +25,11 @@ install:
 	install -m 0755 $(EXEC_FILES) $(prefix)/bin
 
 install-man:
-	install -d -m 0755 $(prefix)/man
+	install -d -m 0755 $(mandir)
 	cd man && \
 	make man && \
-	install -d -m 0755 $(prefix)/man/man1 && \
-	install -m 0644 $(MAN_FILE) $(prefix)/man/man1 && \
-	mandb $(prefix)/man/man1
+	install -d -m 0755 $(mandir)/man1 && \
+	install -m 0644 $(MAN_FILE) $(mandir)/man1
 
 install-all: install install-man
 
@@ -39,11 +39,10 @@ uninstall:
 	rm -f $(EXEC_FILES)
 
 uninstall-man:
-	test -d $(prefix)/man && \
-	cd $(prefix)/man && \
+	test -d $(mandir) && \
+	cd $(mandir) && \
 	rm -f $(MAN_FILE)
-	mandb -f $(prefix)/man/$(MAN_FILE)
-	rmdir --ignore-fail-on-non-empty $(prefix)/man/man1
+	rmdir -rf $(mandir)/man1
 
 uninstall-all: uninstall uninstall-man