Help with Regex

Hello,

I'm facing the following problem: I have to extract patterns from a
variable length expression. The form of the expression in itself is very
simple:

'20 31 64 33 99 12 32 11 44 16 ... 99 41'

Meaning I've sequences of two digits separated by spaces. I just want to
extract it using a "one pass regex".

| rgx |

rgx := RxMatcher forString: '...'

But it seems that VBRegex has no recursion... If I want to have
something like:

rgx subexpression: 2 -> 20
rgx subexpression: 3 -> 31
...
rgx subexpression: n -> 41

what's the simplest way of doing that in one pass?