'port build' different than 'make all'

I have altered the GHC Portfile to have no build section (and no pre-build or post-build sections) and to set (amongst other things):

build.cmd make
build.type gnu
build.args ""
build.target all

(1)
$ sudo port configure
$ cd /opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_ports_lang_ghc/work/ghc-6.6.1
$ sudo make all

(2)
$ sudo port configure
$ sudo port build


I think that running (1) and (2) should be equivalent.  However, when I do this, I do not get the same object files.  Namely, when I install with (1), my GHC works (at least for trivial examples).  When I install with (2), I get weird errors (that I can describe further if requested).  I have built GHC about 25 times (at ~4 hours/build) to narrow it down to this.  Can someone shed some light on why there is any difference?  I think it must be somewhere in my environment, but I can't figure out what - I have at least set the PATHs to be the same.  I am new to Portfile development and was interested in helping to get a good build for GHC 6.6.1 on Leopard.

If any more information is needed, I will happily provide it.  Thanks in advance for any help at all.