This will utilize the ~q ban mask on UnReal IRCd to give you ebtter control over silencing people.

The documentation on how to use this command is in the snippit at the top.

I know it's server specific, but UnReal IRCd is what my server i go on uses, I've seen other UnReal IRCd related stuff on mIRC Script sites before.

; /silence Nick [minutes]
; /silence -u Nick (unsilence)
; /silence [Addr Number:]Nick [minutes]
; /silence Address [minutes]
; /silence -u [Addr Number:]Nick
; /silence Address

; Example:
; /silence bob 5 - Silences bob for 5 minutes
; /silence 2:Bob - Silences the host mask of bob (2nd type)
; /silence *.staff.mugglenet.com 10 - Silences *.staff.mugglenet.com for 10 minutes
; /silence -u 2:bob - Unsilences the host mask of bob (2nd type)
; /silence -u * - Unsilences *!*@* 

Silence { 
  if ($1 == -u) { 
    if ($2) { 
      if ($numtok($2,$asc(:)) > 1) { 
        tokenize 32 $address($gettok($2,2,$asc(:)),$gettok($2,1,$asc(:))) 
        if ($1) { 
          mode $active -b ~q: $+ $1
        }

      }
      else { if ($1) { mode $active -b ~q: $+ $2 } } 
    } 
  }
  else {
    if ($numtok($1,$asc(:)) > 1) { 
      var %nick = $gettoK($1,2,$asc(:)) 
      tokenize 32 $address($gettok($1,2,$asc(:)),$gettok($1,1,$asc(:))) $2
      if ($1) { 
        mode $active +b ~q: $+ $1 
        if ($2) { .timer $+ $1 1 $calc(60 * $2) mode $active -b ~q: $+ $1 } 
      }
    }
    else {
      if ($1) {  
        mode $active +b ~q: $+ $1 | if ($2) { timer $+ $1 1 $calc(60 * $2) mode $active -b ~q: $+ $1 } 
      }
    }
  }
}