Field gets cleared if submit before validated

I have an email field and ajax validation rules by field_validation. If i enter an email address and click submit directly without clicking at another field or somewhere else on the page the clientside validation will get triggered by the submit and the field is validated corretly but after the submit reloaded the page it shows an error that the field is required and not filled. This error is not there if i trigger the validation before submitting the node by clicking at another field.