LinuxQuestions.org - Sendmail error - DSN: Remote protocol error

Hello Friends,

I am getting error in sendmail. Our one of the client trying to send email to his client.
But he is receiving bounce message :

Dec 17 18:28:58 mx10 sendmail[16236]: qBHCwwPJ016236: from=<sender@domain.com>, size=19591, class=0, nrcpts=1, msgid=<01bc01cddc57$29366ab0$7ba34010$@sender@domain.com>, proto=ESMTP, daemon=MTA, relay=202.52.134.60.static-pune.hostin.in [202.52.134.60] (may be forged)
Dec 17 18:28:58 mx10 sendmail[16236]: qBHCwwPJ016236: to=<receipient@domain.com>, delay=00:00:00, mailer=esmtp, pri=49591, stat=queued
Dec 17 18:29:02 mx10 MailScanner[13763]: Logging message qBHCwwPJ016236 to SQL
Dec 17 18:29:02 mx10 MailScanner[15645]: qBHCwwPJ016236: Logged to MailWatch SQL
Dec 17 18:29:23 mx10 sendmail[16265]: qBHCwwPJ016236: ge.com.s5a1.psmtp.com.: SMTP DATA-2 protocol error: 582 This message could not be delivered.
Dec 17 18:29:23 mx10 sendmail[16265]: qBHCwwPJ016236: to=<receipient@domain.com>, delay=00:00:25, xdelay=00:00:04, mailer=esmtp, pri=139591, relay=ge.com.s5a1.psmtp.com. [64.18.4.10], dsn=5.5.0, stat=Remote protocol error
Dec 17 18:29:23 mx10 sendmail[16265]: qBHCwwPJ016236: qBHCx2qg016265: DSN: Remote protocol error

Please help me to solve this.
If anyone know then plz let me know the reason of this error message.

Thanks