aclocal problem

[DaJoob]

I'm trying to make a port, but I'm having a problem with aclocal. Here's 
the section of Makefile related to the problem:

pre-configure:
    cd ${WORKSRC}
    aclocal${USE_AUTOMAKE_VER}

When I run make, I get the error "aclocal19: `configure.ac' or 
`configure.in' is required." If I then manually run aclocal19 in the 
${WORKSRC} directory, I can rerun make and it will work fine, so I'm 
guessing the problem is that aclocal19 is not being run in the correct 
directory. Anyone know what I'm doing wrong?