[keycloak-user] error in keycloak-admin-client

[daniele.capasso at dnshosting.it]

Hello,

i update a keycloak installation from 1.7 to 1.9.1, i upgrade a pom 
dependency for keycloak-admin-client, bat
when i call org.keycloak.admin.client.token.TokenManager.grantToken();

i receive a error
org.codehaus.jackson.map.exc.UnrecognizedPropertyException: Unrecognized 
field "access_token" (Class 
org.keycloak.representations.AccessTokenResponse), not marked as 
ignorable
  at [Source: org.apache.http.conn.EofSensorInputStream at 23b73091; line: 
1, column: 18] (through reference chain: 
org.keycloak.representations.AccessTokenResponse["access_token"])

I used in my project the resteasy-client ver. 3.0.11.Final,  is it 
possible that this library does not match with keycloak-admin-client 
1.9.1-final?