It is likely that all Buddhas attain the Buddhahood via jhana. There is another sutta that describes how the previous Buddha, Kassapa Buddha, attained Buddhahood the same way.
However, there is no need to go through jhanas, for those disciples with high level of wisdom (panna). They are called pannavimutti Arahants.
– Still, no matter how high one’s level of panna is one cannot attain the Buddhahood by one’s own efforts, unless it is a Bodhisattva.
Furthermore, even at the time of the Buddha (before the Enlightenment of the Buddha), there were yogis who were able to get to the highest jhanas (including possibly the five ascetics).
– However, they could not attain Nibbana, because only a Buddha can attain Nibbana via his own efforts.
– One who can get to any jhana, of course can attain Nibbana once he/she comprehends the Four Noble Truths.
These are discussed in detail at the “Samādhi, Jhāna (Dhyāna), Magga Phala” section.