Limit in complete from gal ?

When i compose an e-mail, i use the complete from gal plugged in an external ldap.

Is there a limit of the number of corresponding e-mail adresses displayed by zimbra, according to the first letters i typed ? If yes, is there a way to change this limit ?

I have a stange pb :
Looking for a man with first name "philippe". Zimbra display a number of "philippe"
coming from ldap but the one i search is not displayed. And as the results are in alphabetical order, it let me think that the adress does not exists. But searching by last name give me the answer from the same ldap ?