plantuml-viewer is not rendering "database" keyword

[fdutenho]

@startuml
allow_mixing
class foo1
usecase foo2
database foo3
foo1 -- foo2
@enduml

ends up with
"database foo3
Syntax Error?
did you mean:
database- foo3"

[fdutenho]

"compile" the .puml file into an .png with plantuml.jar works