Sort by custom field is a little crazy here

Hello again, community.
Well, i’m sorting a loop by a custom field using the args

posts_per_page' => 0,
    'meta_key' => 'wpcf-imovel-preco' ,
    'orderby' => 'meta_value',
    'order'=>'ASC'

it works… at some point! then it looses the order and starts again
like this:
1) 120.000,00 2) 121.000,00 3) 130.000,00 4) 35.000,00 5) 36.000,00 and so on…
Well, maybe it has something to do with the , that we use to separate cents and . to thousands…. i know that in english you should write 35,000.00 not 35.000,00, but in brazil we use the second way…
anyone, please, give me some light on this! ??