Here is some advice we collected for translators:
Only commit translated files in your language's directory. The build process is responsible for adding English files in place of the files you have not committed.
Do not commit translated files into the English tree. Double check your files before committing, to be sure that you are committing to the right place.
Use a system to coordinate with the translators in your language. Currently we have two systems used paralelly, the Translators files and the Revision comments. See the section about revision tracking to learn more about this subject.
While translating, you will find errors in the English manual. If you are sure about an error, that should be corrected, please correct the found errors yourself. If you are not sure, whether you found an error or not, please ask on the phpdoc mailing list.
We have the global entities used all over the manuals in global.ent. If you would like to define entities only used in your language, an ideal place for these is your_language/language-defs.ent. See hu/language-defs.ent for an example.
Do not translate entity names, such as &true; or &return.success;. These are there to be replaced by their relevant text. Translating them only cause errors. Similarly do not translate any tags (eg. <computeroutput>) to your language. The contents of comments (eg. the bottom of every file) are also not to be translated.
Always make sure, that the modifications you made to your language's files, are correct. You may introduce illegal characters. Please always do a make test before commiting. Introducing an error in your languages manual can stop the automatic updates online until you correct the error.
If your manual is online at the PHP mirror sites, you can check out the building log of the several downloadable formats and online manuals by downloading the build.log.gz file of your language. For the German translation, this file is: http://www.php.net/de/blog. Substitute "de" with your own language code to see the information about your manual. This file provides you information about the build times, and errors (if there were any). If the manual is not updated online, it is a good idea, to look into this file and see what was the error.
Note, that some browsers like MSIE may uncompress the gz file on the fly and show the log file in the browser window as text. This also means, that if you download this gz file with MSIE, the downloaded file name will still hold the gz extension, while it will be a simple text log file.