[horde] Class 'DOMDocument' not found

[Alexandru David Constantinescu]

Hello

This is my first post on this list and I use this method because google 
don't give me any answer. In short terms my problem is that I can't 
install the horde webmail suite. I've try 3 versions 1.3, 1.2 and 1.08 
all with the same result.
The setup.php hang with message Internally used charset* [iso-8859-1]
PHP Fatal error:  Class 'DOMDocument' not found in 
/usr/local/apache2/htdocs/horde-webmail-1.0.8/lib/Horde/Config.php on 
line ....

All I can find is something about php-xml but my problem is that my php 
v 2.5.2 is installed from source and XML and DOM suport is enable by 
default.
I even try to recompile php and explicit enable those modules but the 
config complains about unknown clause --with-dom
My php -m look like this :

[PHP Modules]
ctype
curl
date
dom
exif
filter
ftp
gd
gettext
hash
iconv
imap
json
libxml
mbstring
mcrypt
mysql
mysqli
openssl
pcre
PDO
pdo_mysql
pdo_sqlite
posix
Reflection
session
SimpleXML
sockets
SPL
SQLite
standard
sysvsem
sysvshm
tokenizer
xml
xmlreader
xmlwriter
zlib

[Zend Modules]

In phpinfo() I see :

	dom
DOM/XML 	enabled
DOM/XML API Version 	20031129
libxml Version 	2.6.26
HTML Support 	enabled
XPath Support 	enabled
XPointer Support 	enabled
Schema Support 	enabled
RelaxNG Support 	enabled

Anyone have a solution to this problem ? Please

alex