From this post on Sebastian Bergmann's blog, we learn about an update to the original O'Reilly "PHP Pocket Reference" (German translation edition) book by Rasmus Lerdorf.

Garvin Hicking has updated the German edition of Rasmus Lerdorf's "PHP Pocket Reference" book for PHP 5 and I wrote the introduction to object-oriented programming chapter for this new edition.

More information here.

This will be the third edition of the book, with some major updates made to include the new features that PHP 5 has to offer. The functions are now categoriezed a bit better to make for quick lookup, and the introduction is reworked to includes some of the updates as well.