5.0.37 ,sql a table still not found

[wang shuming]

Hi,
  from 5.0.27  till now 5.0.37, porblem still like this:

  select  * from  a1,a2
             left join b1 on b1.f1=a1.f1
  where  a2.f2=a1.f2
  // shows  table a1 does not exist.

  if   SQL changes into
      select  * from  a2,a1
             left join b1 on b1.f1=a1.f1
  where  a2.f2=a1.f2
//  SQL runs OK.

Thanks!

Shuming　Wang