make problem

Hi,

what is wrong with the following Makefile?

FILES=  a.in b.in a b
FILESDIR= /tmp/foo

.include <bsd.prog.mk>

.SUFFIXES: .in
.in:
        cp $(.IMPSRC) $(.TARGET)

Given that a.in and b.in exist and 'make' has been executed, 'make install' gives the following error:

# sudo make install
installing DIRS FILESDIR
install  -d -m 0755 -o root  -g wheel  /tmp/foo
install  -o root  -g wheel -m 444  a.in /tmp/foo/a.in
install  -o root  -g wheel -m 444  b.in /tmp/foo/b.in
install  -o root  -g wheel -m 444  a /tmp/foo/a
cp _FILESINS1_a.in _FILESINS1_a
cp: _FILESINS1_a.in: No such file or directory
*** Error code 1

Stop.