i don´t know what IOS version you´re using but this could be a bug, #CSCsq24332 http://www.cisco.com/c/en/us/td/docs/ios/12_2sb/release/notes/122SB_cav3.pdf
There is a specific model of 2960 which is stackeable. http://www.cisco.com/c/en/us/products/collateral/switches/catalyst-2960-series-switches/white_paper_c11-578928.html
this is de filter c6k. As you can see it can't be blocking the syslog messages, and when i run all kind of syslog reports i always get the same, empty reports with 0 records. When i tried to open the syslog.log i couldn't open it because it's too big...