size attribute in input element causes problems

This appears to be incorrect to me.

This is line 69 in my HTML:

<li class="todo"><div class="header">Enter score for League  
games:</div><br/><table><tr><td style="font-weight:bold; border-bottom:1px  
dashed green">Cup</td></tr><tr><td><form method="post"  
action="manage_league_games" style="display:inline"><div  
style="display:inline"> - 19/10/2008 - Team2 <input size="2" type="text"  
name="G1AwayScore" value="0" /> - <input size="2" type="text"  
name="G1HomeScore" value="-1" /> Team1 <input type="hidden"  
name="tableRef" value="cup" /><input type="hidden" name="referer"  
value="admin/index" /><input type="hidden" name="weekRef"  
value="Cup_Final" /><input type="hidden" name="year" value="2008" /><input  
type="hidden" name="G1HomeTeam" value="Team1" /><input type="submit"  
name="Submit" value="Enter" /></div></form></td></tr></table><div  
style="font-style:italic; display:inline"><br/><br /><br /><br/></div></li>

Here's what I get.
The size attribute in the input element causes a problem, but size is  
given in the allowed attributes.

Line 69, Column 353: Attribute size not allowed on XHTML element input at  
this point..
…"text" name="G1AwayScore" value="0" /> - <input size="2" type="text"  
name="G1
Element-specific attributes for element input:
accept
action
alt
autocomplete
autofocus
checked
disabled
enctype
form
list
max
maxlength
method
min
name
pattern
readonly
required
size
src
step
target
type
value