After upgrade from 5.2.4 to 5.2.6 with replace agents from first generation to second incorrect preprocessing starts to happening.

Steps to reproduce:

1. Create perf_counter_en (e.g. perf_counter_en["\ASP.NET Applications(_LM_W3SVC_1_ROOT)\Request Execution Time",60])
2. Add Preprocessing step "Check for not supported value" with "custom on fail set value to 0"
3. Click on item's "Test" screen element and "Get value and test" button to make sure that scenario works fine (item is unsupported and should be set to 0)
4. Click on Execute now (assuming that check is passive)

Result:
Item does not become unsupported in host item's list, however "0" value does not appear in item's history.
Also, i would guess, server (or proxy) still treats this item as unsupported causing extra load on unreachable pollers and putting this item in queue.
Expected:
Value "0" in item history, no extra load on unreachable pollers and no extra elements in queue.
At least that behavior was in 5.2.4 version of installed configuration: server, proxy and agents (first generation).