It seems that Islamist activism may be similar to the anatomy of a riot. Very generally (and definitely with ommission of finer points), there seems to be a nexus between the youths who compose the rank-and-file membership of the movement and the overall leadership. The nexus seems to be a teacher, and not necessarily at a madrassa, similar to the "riot leaders" who always seem to be around when things start to get bad.
However, whether the neutralization of the teacher will prevent the spread of the network has not been properly explored.
Kalimaya-e-Jamaat, hitherto unknown (for me anyway), is led by Abdul Majid of the Char Fashion Government College in Bhola, Barisal (I assume this is the same Charfasson sub-district annontated on the map). Six of his "disciplies" were arrested in Feni district Chittagong, they ranged in age from 18 to 26, and one, Samsuddin, completed his Master's degree at a government college.
Majid, who also has a Master's degree, was charge-sheeted in the 17 August 2005 bombings but is out on bail. He claims to have over 400 other activists but none are involved in anything "illegal" (Daily Star).
These arrests cast further doubt on the idea that Islamism is only attractive to those with poor educational attainment. Of note, Abdul Majid is not a teacher at a madrassa, he is employed at a government college. Additionally, unlike "Boma Mizan" of the JMB who had fairly high status, it doesn't appeart that Samsuddin (who attained a Master's) was nothing more than a cadre.
This reality should force many people in the Bangladeshi government (not to mention India, the U.S., and UK) to pause and study the implications. For one, it means that the message is not simply about duping uneducated masses. Regardless of the type of adherents, this reality does not legitimize the Islamist message and nor should governments treat the Islamist message as reasonable.
While there are aspects of Bangladesh politics and governance that could be substantial reformed the removal of the system is not the answer. Moreover, as the JMB saga illustrated, some Islamist outfits seek only to empower themselves and their cadre. What should happen is governmental reform taking into account the valid grievances of those who believe in the Islamist message.
Finally, these immediate arrests should be studied over the long term. Would the arrest of Abdul Majid effectively silence the Kalimaya-e-Jamaat? The JMB survived the deaths of many of their leaders (in particular Abdur Rahman and Siddiqul Islam) but would it have if the mouth-pieces, prostylitizers, and preachers were also arrested?
However, this avenue should be approached cautiously. There is a fine line between freedom of speech and speech inciting violence.