Why does package 1.0 DTD keep changing?

Hi, Each time I prepare a release of some of my packages, I naturally want to validate the package description file against the DTD. And a weird thing, each time this validation fails. The previous time this was due to the fact that package 1.0 DTD was itself invalid. This time, among the changes made to the DTD to (probably) get rid of PECL-related stuff [1], there is the following, <release> tag definition went from <!ELEMENT release (version,date,license,state,notes,warnings?,((deps?,configureoptions?,provides*,filelist?)|(configureoptions?,provides*,filelist?,deps?)))> to <!ELEMENT release (version,date,license,state,notes,warnings?,provides*,deps?,configureoptions?,filelist)> This effectively makes all package.xml files having <deps> after <filelist> invalid. Is it normal to get such BC-breaking changes in a supposedly stable format? [1] http://cvs.php.net/diff.php/pearweb/public_html/dtd/package-1.0?r1=1.11&r2=1.12&ty=h