diff --git a/rhodecode/__init__.py b/rhodecode/__init__.py
--- a/rhodecode/__init__.py
+++ b/rhodecode/__init__.py
@@ -51,7 +51,7 @@ PYRAMID_SETTINGS = {}
 EXTENSIONS = {}
 
 __version__ = ('.'.join((str(each) for each in VERSION[:3])))
-__dbversion__ = 80  # defines current db version for migrations
+__dbversion__ = 81  # defines current db version for migrations
 __platform__ = platform.system()
 __license__ = 'AGPLv3, and Commercial License'
 __author__ = 'RhodeCode GmbH'
diff --git a/rhodecode/lib/dbmigrate/versions/081_version_4_10_0.py b/rhodecode/lib/dbmigrate/versions/081_version_4_10_0.py
new file mode 100644
--- /dev/null
+++ b/rhodecode/lib/dbmigrate/versions/081_version_4_10_0.py
@@ -0,0 +1,50 @@
+import logging
+
+from sqlalchemy import *
+from sqlalchemy.engine import reflection
+from sqlalchemy.dialects.mysql import LONGTEXT
+
+from alembic.migration import MigrationContext
+from alembic.operations import Operations
+
+from rhodecode.model import meta
+from rhodecode.lib.dbmigrate.versions import _reset_base, notify
+
+log = logging.getLogger(__name__)
+
+
+def upgrade(migrate_engine):
+    """
+    Upgrade operations go here.
+    Don't create your own engine; bind migrate_engine to your metadata
+    """
+    _reset_base(migrate_engine)
+    from rhodecode.lib.dbmigrate.schema import db_4_9_0_0
+
+    if migrate_engine.name in ['mysql']:
+
+        context = MigrationContext.configure(migrate_engine.connect())
+        op = Operations(context)
+
+        user_log_table = db_4_9_0_0.UserLog.__table__
+        with op.batch_alter_table(user_log_table.name) as batch_op:
+
+            action_data_json = user_log_table.columns.action_data_json
+            user_data_json = user_log_table.columns.user_data_json
+
+            batch_op.alter_column(action_data_json.name, type_=LONGTEXT)
+            batch_op.alter_column(user_data_json.name, type_=LONGTEXT)
+
+    # issue fixups
+    fixups(db_4_9_0_0, meta.Session)
+
+
+def downgrade(migrate_engine):
+    meta = MetaData()
+    meta.bind = migrate_engine
+
+
+def fixups(models, _SESSION):
+    pass
+
+
diff --git a/rhodecode/model/db.py b/rhodecode/model/db.py
--- a/rhodecode/model/db.py
+++ b/rhodecode/model/db.py
@@ -43,6 +43,7 @@ from sqlalchemy.orm import (
 from sqlalchemy.sql.expression import true
 from sqlalchemy.sql.functions import coalesce, count  # noqa
 from sqlalchemy.exc import IntegrityError  # noqa
+from sqlalchemy.dialects.mysql import LONGTEXT
 from beaker.cache import cache_region
 from zope.cachedescriptors.property import Lazy as LazyProperty
 
@@ -1233,8 +1234,8 @@ class UserLog(Base, BaseModel):
     action_date = Column("action_date", DateTime(timezone=False), nullable=True, unique=None, default=None)
 
     version = Column("version", String(255), nullable=True, default=VERSION_1)
-    user_data = Column('user_data_json', MutationObj.as_mutable(JsonType(dialect_map=dict(mysql=UnicodeText(16384)))))
-    action_data = Column('action_data_json', MutationObj.as_mutable(JsonType(dialect_map=dict(mysql=UnicodeText(16384)))))
+    user_data = Column('user_data_json', MutationObj.as_mutable(JsonType(dialect_map=dict(mysql=LONGTEXT()))))
+    action_data = Column('action_data_json', MutationObj.as_mutable(JsonType(dialect_map=dict(mysql=LONGTEXT()))))
 
     def __unicode__(self):
         return u"<%s('id:%s:%s')>" % (