Testopia:Documentation:XMLRPC:viewall

Unless you explicitly tell TestCase.list (and other .list methods) how many results to return, it will default to 25. You can control the size with the page_size and page parameters (need example), or by setting the viewall parameter to get all records:

query = java.util.Hashtable();
query.put("plan_id", 28);
query.put("planidtype", "equals");
query.put("case_status_id", 2);
query.put("isautomated", 1);
query.put("viewall", 1);
params = java.util.Vector()
params.add(query)
result = client.execute("TestCase.list", params)