Registration forms clearing when a field is not filled in correctly...

Good morning,

I was just testing a clients registration form and entered a word instead of a number in one field, it gave an error but also cleared over half the fields. These fields are text areas and as such would discourage people from registering when they have to retype them. Can anyone shed any light on how to prevent the fields from clearing when an error occurs?
Also, it is giving the error "Not an integer", how can I change this to tell the visitor that it should be a number?
Joomla 2.5.19
CB 1.9.1
Thank you,
Cassandra