knoppix@Microknoppix:~$ perl -E '
> $dateStr = q{ 2 0 1 2 - 7 - 2 7  9 : 3 7 : 3 1 };
> $dateStr =~ s{\s(?!\s)}{}g;
> say $dateStr;'
2012-7-27 9:37:31
knoppix@Microknoppix:~$