Limitation of FetchXML regarding 'in' operator

Hi,

you can use custom filter for lookups in JavaScript, thus you can limit the data sets selectable in the lookup. E.g.:

Xrm.Page.getControl("new_userlookup").addCustomFilter(filter);

where the variable "filter" is a FetchXML like this:

<filter type='and'><condition attribute='domainname' operator='in'><value>mydomain\user1</value><value>mydomain\user2</value><value>mydomain\user3</value>
...</condition></filter>

As you can see the filter consists of several specific data sets.

I Wonder if there's a limitation when using this kind of query - is it possible to specify unlimited data sets inside the FetchXML or this there any kind of limitation (e.g. only 50 data sets allowed etc.)? This is a general question, the code above is only a sample.

With best regards,

Michael