Login on SSO stg fails

When attempting to log in using SSO staging, the service fails.
Sometimes first login is OK, but every next login fails.

Used on server: http://buildtracker-stg.jboss.org/ (IP 10.34.40.171) or http://buildtracker-dev2.jboss.org/
After clicking on User tab, the user is redirected to SSO and it fails with message: "JBoss Developer Login is unavailable There was an error trying to complete your request. Try it later please. ".
Example of used request: https://sso-stg.jboss.org/login?SAMLRequest=jZJLb4MwEIT%2FCvLdAQKkwQpINKhqpD6ihPbQS2VgSdyCTb2mj39fAq2UXKLcLPubndmRF8ibumVJZ%2FZyAx8doLG%2Bm1oiGx4i0mnJFEeBTPIGkJmCbZP7OzadOKzVyqhC1WSUnIc5ImgjlCRW8n9cKoldA3oL%2BlMU8LS5i8jemJbZdt6JujSaF%2B%2BgKZrd5C1XiBOld3bXq4mV9lGF5Icxowh7FaI6hYm1SiOySl%2FdahbMwyCkpeeH1IfQo3O3vKJFnldTf%2B4AVNMeRuxgJdFwaSIyddyAOi51gsz1mOMx35%2FMnPCFWOu%2Fza%2BFLIXcnd88HyFkt1m2puvHbUasZ9A4JO8BEi8OZbPBXB%2FVf2mh8WWdLewjm9GzZQ%2F93FW6VrUofqykrtXXUgM3EBGjOyDWjdINN%2BeTHG5ESasBZX0AiQKkIXY8Wp7%2Br%2FgX

Second example of invalid request:
https://sso-stg.jboss.org/login?SAMLRequest=jZLdT4MwFMX%2FFdL38uVgWzNIcMRIMpVs0wdfTIG7rQot9hY%2F%2FnsZaDJflr017e%2Fcc%2B5JF8ibumVJZw5yDe8doLG%2BmloiGx4i0mnJFEeBTPIGkJmSbZK7FfNtl7VaGVWqmoyS8zBHBG2EksRK%2Fo5LJbFrQG9Af4gSHteriByMaZnjFJ2oK6N5%2BQaaotnbr4VCtJXeO12vJlbaRxWSH8eMIuxViOo%2FTKwsjUiWvrjldAZzCCjMdzM64eWUFoG%2Fo35wFbizkAdhNe1hxA4yiYZLExHf9QLqetQNt57LJhPmhbbnhc%2FEyn83vxayEnJ%2FfvNihJDdbrc5zR82W2I9gcYheQ%2BQeHEsmw3m%2BqT%2BSwuNL%2Bts4ZzYjJ4tu%2B%2FnZmmual