We\'re getting ready to translate our PHP website into various languages, and the gettext support in PHP looks like the way to go.
All the tutorials I see recommend
In a word don't do this.
The same word/phrase in English can often enough have more than one meaning, and each meaning a different translation.
Define mnemonic ids for your strings,and treat English as just another language.
Agree with other posters that id numbers in code are a nightmare for code readability.
Ex localisation engineer