Entity Syntax Differences with Google Search Appliance

Thunderstone Search Appliance Manual

The XML entity schema is largely compatible with that of the Google Search Appliance, to facilitate migration. However, there are some differences:

The <case_sensitive> element was added. On the Google Search Appliance, case sensitivity would be set via the Case sensitive GUI element.
The <apply_case> element was added. On the Google Search Appliance, this would be set via the Store entities as GUI element, under the Adjustments tab.
REX syntax is also supported for <pattern>s.
RE2 syntax is not supported for <pattern>s on some older platforms. These platforms will give the error message "REX: RE2 not supported on this platform" when uploading an entity file containing RE2 <pattern>s. (Windows, Linux 2.6 and later versions except i686-unknown-linux2.6.17-64-32 are supported.)
regex_tagged_as_first_group is not supported for REX expressions, as the \P and \F operators can be used in the <pattern> to indicate what to store.
Composite entities are not currently supported. Thus there is also no Transient setting either.