In all 8.12 and 8.13 versions of sendmail, cf/feature/msp.m4 unconditionally sets confDELIVERY_MODE to interactive, thereby overriding any attempt to set confDELIVERY_MODE in submit.mc. The attached (simple, one-line) patch corrects this issue. (I've filed this bug against FC5, but this applies to all FC and RHEL releases that contain sendmail 8.12 or sendmail 8.13.) Additionally, I've submitted a bug report (plus this patch) upstream to sendmail-bugs-2006.
Created attachment 127080 [details] Patch to fix the bug with cf/feature/msp.m4.
Bah, my bad--this patch won't work, because msp.m4 can't conditionally set confDELIVERY_MODE, because confDELIVERY_MODE will always be set to something (either what was specified in submit.mc, or the default of "background") by the time the macros in msp.m4 are evaluated. The *only* way to override the confDELIVERY_MODE in submit.mc is to ensure that it is defined after FEATURE(`msp'): FEATURE(`msp')dnl define(`confDELIVERY_MODE', `defer') This works.