tcp v4 csum failed appear after 2.4.18 -2.4.26

We have 2 machines which have "hw tcp v4 csum failed" after upgrading from 2.4.18 to 2.4.26

If we boot again into the 2.4.18 kernel, we no longer see these "hw tcp v4 csum failed" errors.

What has changed, causing the tcp csum errors appear in 2.4.26?

Thanks
-tim