while (@t = split /\s+/, <DATA>){
	push (@{$h{$t[0]}{$t[1]}}, "$t[2]:$t[3]");
}

foreach $k (sort keys %h){
	print "$k ", join(' ', map {$_, @{$h{$k}{$_}}} sort keys %{$h{$k}}),"\n";
}


__DATA__
id1    name1 cat1  catname1
id1    name1 cat2  catname2
id2    name2 cat3  catname3
id3    name3 cat1  catname1
id3    name3 cat4  catname4