The package description (i.e., pkg-desc/pkg-description.txt in the OXT) from the current v0.9.5 release of the NumberText extension offers these helpful examples:
Usage
=numbertext(5) → “five”
=numbertext(5;"de") → “fünf”
=moneytext(5;"USD") → “five dollars”
=moneytext(5;"HUF";"hu") → “öt forint”
Help for extra functions and modules of the default language:
=numbertext("help")
Examples for using extra functions:
=moneytext(1; "ord"; "en") (English ordinal numbers) → “first”
=moneytext(999; "ord2"; "en") (English ordinal abbreviations) → “1st”
I can confirm that under Debian 7 x86_64 using v4.1.4.2 Build ID: 0a0440ccc0227ad9829de5f46be37cfb6edcf72 and Crunchbang 11 x86_64 using v4.2.2.1 Build ID: 3be8cda0bddd8e430d8cda1ebfd581265cca5a0f this extension is still working as expected.