The version of Builder used for rxml templates in Rails 1.0 doesn’t escape attribute values when they are written to the output. This means characters such as double quotes in the attribute values will cause invalid XML documents to be generated.
To avoid having to manually escape every attribute value in rxml templates, I’ve put together a plugin that fixes this issue. Download rails_fixes.zip and extract it to your vendor/plugins directory (to create a new rails_fixes directory). The plugin replaces the _insert_attributes method of Builder::XmlMarkup with one that escapes the values.