Hibernate not persisting enums (as String)

Question

I'm trying to do simple thing, save with Hibernate enum value as string. My mapping looks like this:

@Entity
@Table(name = "CONTRACTOR")
public class Contractor
{
    //some unreleated columns...

    @OneToMany(fetch = FetchType.LAZY, cascade = {CascadeType.PERSIST, CascadeType.MERGE, CascadeType.REMOVE}, mappedBy = "contractor")
    private List<ContractorGeoAvailability> geoAvailabilities;

    //getters, setters
}

Entity with anum:

@Entity
@Table(name = "CONTRACTOR_GEO_AVAILABILITY")
public class ContractorGeoAvailability
{
    @Id
    @Column(name = "ID")
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long id;

    @JoinColumn(name = "CONTRACTOR_ID")
    @ManyToOne(fetch = FetchType.LAZY)
    private Contractor contractor;

    @Column(name = "TYPE")
    @Enumerated(EnumType.STRING)
    private GeoAvailibilityType geoAvailibilityType;

    @Column(name = "VALUE")
    private String value;

    ....
}

And enum:

public enum GeoAvailibilityType
{
    DISTRICT,
    CITY,
    VOIVODESHIP,
    COUNTRY
}

From submitted form I receive correct values (HTTP POST):

------WebKitFormBoundary1huaDyI1dvn9KGnI
Content-Disposition: form-data; name="geoAvailibilities[0].type"

CITY
------WebKitFormBoundary1huaDyI1dvn9KGnI
Content-Disposition: form-data; name="geoAvailibilities[0].value"

test
------WebKitFormBoundary1huaDyI1dvn9KGnI
Content-Disposition: form-data; name="geoAvailibilities[1].type"

VOIVODESHIP
------WebKitFormBoundary1huaDyI1dvn9KGnI
Content-Disposition: form-data; name="geoAvailibilities[1].value"

Even value is correctly binded with DTO object:

ContractorRegisterForm{.... geoAvailibilities=[GeoAvailibility{type=CITY, value='test'}, GeoAvailibility{type=VOIVODESHIP, value='test321'}], profile=null}

but somehow during persisting enum's value is lost:

21:55:59,123 INFO  [stdout] (http--127.0.0.1-8080-3) Hibernate: 
21:55:59,123 INFO  [stdout] (http--127.0.0.1-8080-3)     insert 
21:55:59,123 INFO  [stdout] (http--127.0.0.1-8080-3)     into
21:55:59,123 INFO  [stdout] (http--127.0.0.1-8080-3)         CONTRACTOR_GEO_AVAILABILITY
21:55:59,123 INFO  [stdout] (http--127.0.0.1-8080-3)         (CONTRACTOR_ID, TYPE, VALUE, ID) 
21:55:59,124 INFO  [stdout] (http--127.0.0.1-8080-3)     values
21:55:59,124 INFO  [stdout] (http--127.0.0.1-8080-3)         (?, ?, ?, ?)
21:55:59,124 TRACE [org.hibernate.type.descriptor.sql.BasicBinder] (http--127.0.0.1-8080-3) binding parameter [1] as [BIGINT] - 19
21:55:59,124 TRACE [org.hibernate.type.descriptor.sql.BasicBinder] (http--127.0.0.1-8080-3) binding parameter [3] as [VARCHAR] - test
21:55:59,124 TRACE [org.hibernate.type.descriptor.sql.BasicBinder] (http--127.0.0.1-8080-3) binding parameter [4] as [BIGINT] - 20
21:55:59,125 INFO  [stdout] (http--127.0.0.1-8080-3) Hibernate: 
21:55:59,125 INFO  [stdout] (http--127.0.0.1-8080-3)     insert 
21:55:59,125 INFO  [stdout] (http--127.0.0.1-8080-3)     into
21:55:59,125 INFO  [stdout] (http--127.0.0.1-8080-3)         CONTRACTOR_GEO_AVAILABILITY
21:55:59,125 INFO  [stdout] (http--127.0.0.1-8080-3)         (CONTRACTOR_ID, TYPE, VALUE, ID) 
21:55:59,126 INFO  [stdout] (http--127.0.0.1-8080-3)     values
21:55:59,126 INFO  [stdout] (http--127.0.0.1-8080-3)         (?, ?, ?, ?)
21:55:59,126 TRACE [org.hibernate.type.descriptor.sql.BasicBinder] (http--127.0.0.1-8080-3) binding parameter [1] as [BIGINT] - 19
21:55:59,126 TRACE [org.hibernate.type.descriptor.sql.BasicBinder] (http--127.0.0.1-8080-3) binding parameter [3] as [VARCHAR] - test321
21:55:59,126 TRACE [org.hibernate.type.descriptor.sql.BasicBinder] (http--127.0.0.1-8080-3) binding parameter [4] as [BIGINT] - 21

It looks like the enum value is completly ignored by Hibernate, as it persists 1st, 3rd and 4th parameter not 2nd one (see binding parameter [.]). Could someone help me with that?