Attached is a patch that adds components support to multistrap (fantasic tool btw).

Example config section:

[Nexenta]
source=http://apt.nexenta.org
suite=hardy-unstable
keyring=nexenta-keyring
components=main contrib non-free

Pretty simple stuff really.

Thanks,
Andy

--- /export/home/andy_js/emdebian-rootfs/emdebian-rootfs-2.0.2/em_multistrap	2009-03-29 17:28:49.000000000 +0200
+++ ./em_multistrap	2009-07-29 05:52:51.172145140 +0200
@@ -24,7 +24,7 @@
 use vars qw/ $progname $ourversion $dstrap $extra @aptsources
  @archives $deb $cachedir $config_str %packages $retval $str $retries
  $dir $include $arch $foreign $suite $url $unpack $sourcedir
- @e $sourcesname $libdir $dpkgdir @debootstrap %suites $mirror $etcdir
+ @e $sourcesname $libdir $dpkgdir @debootstrap %suites %components $component $mirror $etcdir
  $repo @dirs @touch %sources $section %keys $host $key $value $type
  $file $config $tidy $noauth $keyring %keyrings /;
 $progname = basename($0);
@@ -80,6 +80,7 @@
 %sources=();
 %packages=();
 %suites=();
+%components=();
 %keyrings=();
 @aptsources=();
 foreach $section (sort keys %keys)
@@ -108,6 +109,11 @@
 		$sources{$section}=$keys{$section}{'source'};
 		$packages{$section}=$keys{$section}{'packages'};
 		$suites{$section}=$keys{$section}{'suite'};
+		$components{$section}=$keys{$section}{'components'};
+		if (!$components{$section})
+		{
+			$components{$section}='main';
+		}
 		$keyrings{$section}=$keys{$section}{'keyring'};
 	}
 }
@@ -179,9 +185,10 @@
 			or die "Cannot open sources list $!";
 		$mirror = $sources{$aptsrc};
 		$suite = $suites{$aptsrc};
+		$component = $components{$aptsrc};
 		print SOURCES<<END;
-deb $mirror $suite main
-deb-src $mirror $suite main
+deb $mirror $suite $component
+deb-src $mirror $suite $component
 END
 		close SOURCES;
 	}