analyzing a log file FROM time TO time

[graziano]

Hello

I have a maillog.txt file like this

Mar-15-07 07:49:58 82.235.17.23 <[e-mail]>..blah
Mar-15-07 07:52:50 82.235.17.23 <[e-mail]>..blah
...
Mar-20-07 01:52:50 82.235.17.23 <[e-mail]>..blah

In this log , I want search the first line with the value "delayed rejected" AND the ip "82.235.17.23" ONLY in the time log interval FROM
Mar-15-07 07:49:58 TO (Mar-15-07 07:49:58)+28 hours .

Can you give me some suggestion to write this code ?
(I need this to check email rejected from my greylisting filter in 28 hours.)

Thanks