[Exim] Question about reject logs...

I'm not sure what to make of this info in my reject log... Although I'm these
are probably Spam, why are they being rejected?

2003-04-14 03:49:26 rejected HELO from [211.238.93.109]: syntactically invalid
a
rgument(s): mail_server.cashspeed.co.kr
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2003-04-14 03:54:18 rejected EHLO from [161.132.223.30]: syntactically invalid
a
rgument(s): rt_servi01.vialsi.com
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2003-04-14 03:54:18 rejected HELO from [161.132.223.30]: syntactically invalid
a
rgument(s): rt_servi01.vialsi.com
------------------------------------------------------------------------------
2003-04-14 03:56:13 rejected EHLO from [211.238.93.109]: syntactically invalid
a
rgument(s): mail_server.cashspeed.co.kr
------------------------------------------------------------------------------
2003-04-14 03:56:13 rejected HELO from [211.238.93.109]: syntactically invalid
a
rgument(s): mail_server.cashspeed.co.kr