This is true, but Cleaver does not rhyme with Clever.
I'm a Kiwi, we're renowned for butchering English.
Or as we call it, Unglush.
For some fun examples, here's a video made by Australians parodying our accent[0].
And here's another one[1], although what's funny as a Kiwi is to me it just sounds like Australians saying "deck", but to them it sounds like Kiwis saying "dick". But then once when I asked my friend's Australian partner to pass me a pen once, she was confused until I pronounced it (to me) as "peeen", which felt like I was taking the piss out of her accent, but she understood me then, she had thought I was asking for a pin...
Oh, and here's one from the Flight of the Conchords playing on our accent and American comprehension thereof.[2]
I've never heard cleaver pronounced "clever" (so far in my life), but then, lever is often pronounced here in a way that rhymes with "cleaver" (i.e., "leaver" vs. "lever") so I can entirely understand that the pronunciation of cleaver could change to clever in other countries' English.
Ah, English, the mongrel cur of languages.
[0]: https://www.youtube.com/watch?v=ZdVHZwI8pcA
Specifically that both sound like kleh-ver not that both sound like klee-ver just to be clear, because as long as we're only writing text here and the very topic is ambiguity about how a word sounds, I notice that by the normal rules "clever" should be expected to sound like klee-ver, which starts to make this conversation a bit funny.