After running symfony propel-build-all on a new symfony installation got this error. The solution is to install the php-xml rpm (deb).
[root@devel2 cms]# symfony propel-build-all
>> schema converting "/home/sfprojects/cm...lugin/config/schema.yml" to XML
>> schema putting /home/sfprojects/cms/pl...erated-sfGuardPlugin-schema.xml
>> file+ config/generated-sfGuardPlugin-schema.xml
>> file- /home/sfprojects/cms/plugins/sf...erated-sfGuardPlugin-schema.xml
Buildfile: /usr/share/pear/symfony/vendor/propel-generator/build.xml
[resolvepath] Resolved /home/sfprojects/cms/config to /home/sfprojects/cms/config
propel-project-builder > check-project-or-dir-set:
propel-project-builder > check-project-set:
propel-project-builder > set-project-dir:
propel-project-builder > check-buildprops-exists:
propel-project-builder > check-buildprops-for-propel-gen:
propel-project-builder > check-buildprops:
propel-project-builder > configure:
[echo] Loading project-specific props from /home/sfprojects/cms/config/propel.ini
[property] Loading /home/sfprojects/cms/config/propel.ini
propel-project-builder > om:
[phing] Calling Buildfile '/usr/share/pear/symfony/vendor/propel-generator/build-propel.xml' with target 'om'
[property] Loading /usr/share/pear/symfony/vendor/propel-generator/./default.properties
propel > check-run-only-on-schema-change:
propel > om-check:
propel > om:
[echo] +------------------------------------------+
[echo] | |
[echo] | Generating Peer-based Object Model for |
[echo] | YOUR Propel project! (NEW OM BUILDERS)! |
[echo] | |
[echo] +------------------------------------------+
[phingcall] Calling Buildfile '/usr/share/pear/symfony/vendor/propel-generator/build-propel.xml' with target 'om-template'
[property] Loading /usr/share/pear/symfony/vendor/propel-generator/./default.properties
propel > om-template:
[propel-om] Target database type: mysql
[propel-om] Target package: lib.model
[propel-om] Using template path: /usr/share/pear/symfony/vendor/propel-generator/templates
[propel-om] Output directory: /home/sfprojects/cms
[propel-om] Processing: schema.xml
PHP Fatal error: Class 'DomDocument' not found in /usr/share/pear/symfony/vendor/propel-generator/classes/propel/phing/AbstractPropelDataModelTask.php on line 406