Edit: After half day, my wife’s Mac started having the same problem. I have then applied the solution that I found in the Apple
Get Siri On Your iPhone via Jailbreak Using H1siri –
We have seen the Siri dictation tweak which allowed you to port Siri over to your iPhone but you could only use it with dictation. Now H1Siri tops it all , It is reported to allow you to port Siri to your iPhone 4. The tweak can be found in Cydia by Select Manage > Sources > Edit in Cydia, add the sources and do a search for H1Siri.