When listing some possibilities that an entailed estate holder might pursue to take care of his family financially, I threw in the possibility of breaking an entail parenthetically because it would no longer be an option but wanted to note that it was a possibility at one time. In answering Adrian's qualms, I was trying to clear up my reasoning behind it but wasn't sure that I had based my response on entirely correct information. I have now located the book I was reading earlier this year and would like to share a part of the section I was referencing. I am not as good at imparting large chunks of legal information as I would like to be so I will be mostly quoting. It will probably run a bit long but should be worth it if you're interested in such things. It's very readerly and applies its context to P&P. It comes from a book that is a student casebook to issues, sources and historical documents from Greenwood Press from their "Literature in Context" Series.

"Strict settlements often included provisions for the financial care of widows of deceased heads of houses, for marriage portions of daughters, and younger sons' portions to help them establish themselves in a profession or buy smaller estates of their own. Such provisions were intended to insure that the estate did indeed provide for the family as a whole, while maintaining the integrity of the basic estate as a viable entity, a core around which the family could define itself through many generations.

That there is a breakdown in provision for Mrs. Bennet and her daughters after Mr. Bennet's death is directly linked to the fact that the inheritance of the Bennet estate is determined by strict settlement, the "entailment" that Mrs. Bennet rails against so vehemently in the novel. But the existence of the entailment, though contributing to the problem, is not the full cause of it.

Reading the novel nearly two hundred years after if was written we generally accept the book's insistence that it is the nature of the entail to be unbreakable... But in fact, Austen's emphasis on the significance of the entail in the lives of the Bennet women can be read in a much more complicated way, as Austen's contemporaries would have been well aware. Had Mr. Bennet used sufficient foresight, he might well at an earlier time in his life have been able to break an entail of the kind placed on the Longbourn estate, thereby managing to provide for his wife and daughters. Even if he had not succeeded in breaking the entail, however, he could have made other provisions for his daughters... [Comments on saving money].

...The time to "do something or other" was well in the past by the time the action of the novel takes place. Mr. Bennet might, however, have been able to have broken the entail by joining with his father in a legal process called "common recovery" earlier in his life.

Common recovery of an estate involves what is essentially a fictitious lawsuit that enables the present tenant (legally the "life tenant") and the heir (legally the "tenant in tail") of the property to join together to break the entailment in order to resettle the property in a manner more fitting to the present conditions of the estate and family. Such actions were usually taken either at the time the heir came of age (twenty-one) or at the time of the heir's marriage settlement. Mr. Bennet may, therefore, have had the opportunity to cooperate with his father in a common recovery suit on Longbourn, then the estate of which his father was life tenant and himself tenant in tail. With sufficient forethought, they could have revised the settlement in such a way as to adequately provide for Mr. Bennet's heirs of both genders, either through making the entail general (which would enable the daughters to inherit---a legally appropriate move, though not a conventional one) or through providing in the new settlement greater financial security for the daughters in the event that Mr. and Mrs. Bennet did not produce the expected son. Instead, if the Bennet men had opportunity to resettle the estate (and not all generations in a family did) they clearly did not consider the possibility or exclusively female children and did not revise the settlement adequately to provide for that contingency." (Teachman)

The next paragraph goes on to note that Mr. Bennet would not be exclusively responsible for the current marriage settlements because both fathers would have drawn up the documents and Mr. Bennet would have likely conceded to the authority of his father although I believe, since he had to sign them, he had to right to make requests or cite disagreements. There is further comment on Mr. Bennet's thoughts of the financial situation of his family but that is beyond our present schedule.

I know when I first read P&P I did not have any understanding of property laws in England at this time and I must say it took a while to get a handle on it, at least enough as it applies to JA's works. The above section, by using P&P to explain things, helped to further my understanding. Hope it helps others as well. :) Thanks for bearing with me.