XML Schema failed on transaction when several layer's prefix

[ol]

If there's several layers's prefix in tinyows.config, then describeFeatureType is not 'simple' then libxml2 failed to deal with such a schema then tinyows stop with 'Xml is'nt valid'

checked with lixml2 2.7.5 and 2.7.7

libxml2 error message:

Internal error: xmlSchemaBucketCreate, failed to add the schema bucket to the hash.
Internal error: xmlSchemaParse, An internal error occured.

[ol]

Fix as r297

Caution, now as the typename is explicitly passed in URL, if there's more than one prefix, Typename could not contains special chars like é.

So all CITE layers including EntitéGénérique? must belong to a single prefix on config file.