Translation contact fields form

I have a problem when I try to translate the name of the field from the contact form (like personal information, first name, last name, phone, etc.). I tried to translate using Language area but even if I did all the changes there, in the contact form it displays the original names in english. Maybe I did not look in the right place. Thank you for any idea!

In admin goto section Users, subsection Profiles.

Change the field names and click update (1.3.5) or save (2.0). For other languages, change to desired language first then change field names.

Thank you for the answer !

Probably you are right but still I did not succeed to change anything.

Under user profile I have all thye fields showed but just the “delete” option and is not active. When I tried to modify the field name directly I got the error:

Fatal error: Cannot use string offset as an array in /home/pamro/public_html/var/compiled/admin/%%E4^E42^E4252AD1%%mainbox.tpl.php on line 13

I tried to add new fields and it worked but still I cannot deactivate the original fields in english.

Could be an installation fault?

For those that have this kind of problem, you can edit the fields names under Content / Pages / Contact us (form).