یک نفر نبود جواب منو بده........
خودم یک چیزایی پیدا کردم ولی دقیق متوجه گزینه اولش نشدم

I needed a XMLReader and XMLWriter again, so I've tried to find a solution. And it is very easy:

1. Add utterramblings repo to your CentOs (see here)
2. Run yum install php-xml
3. Done
(it works with lighty version of lxadmin, as it has php compiled with '--enable-xmlreader=shared'. Afaik lxadmin with apache has php compiled with '--disable-xmlreader' so it should not work. Not checked though)